Geominerals/Silicates

From Wikiversity
Jump to navigation Jump to search
Crystals of perovskite occur on a matrix. Credit: Robert M. Lavinsky.{{free media}}
An optical image of the Tenham L6 chondrite in thin section USNM 7703 where bridgmanite is identified in a shock vein by the arrow. Credit: Oliver Tschauner, Chi Ma, John R. Beckett, Clemens Prescher, Vitali B. Prakapenka, George R. Rossman.{{fairuse}}

The geominerals of silicates is an effort to determine which silicates are on Earth and the geochemical reason why from a thermodynamics perspective.

Silicate perovskite is either (Mg,Fe)SiO
3
(the magnesium end-member is called bridgmanite[1]) or CaSiO
3
(calcium silicate) when arranged in a perovskite structure. Silicate perovskites are not stable at Earth's surface, and mainly exist in the lower part of Earth's mantle, between about 670 and 2,700 km (420 and 1,680 mi) depth. They are thought to form the main mineral phases, together with ferropericlase.

The existence of silicate perovskite in the mantle was first suggested in 1962, and both MgSiO
3
and CaSiO
3
had been synthesized experimentally before 1975. By the late 1970s, it had been proposed that the seismic discontinuity at about 660 km in the mantle represented a change from spinel structure minerals with an olivine composition to silicate perovskite with ferropericlase.

Natural silicate perovskite was discovered in the heavily shocked Tenham meteorite.[2][3] In 2014, the Commission on New Minerals, Nomenclature and Classification (CNMNC) of the International Mineralogical Association (IMA) approved the name bridgmanite for perovskite-structured (Mg,Fe)SiO
3
,[1] in honor of physicist Percy Williams Bridgman, who was awarded the Nobel Prize in Physics in 1946 for his high-pressure research.[4]

The perovskite structure (first identified in the mineral perovskite occurs in substances with the general formula ABX
3
, where A is a metal that forms large cations, typically magnesium, ferrous iron, or calcium. B is another metal that forms smaller cations, typically silicon, although minor amounts of ferric iron and aluminum can occur. X is typically oxygen. The structure may be cubic, but only if the relative sizes of the ions meet strict criteria. Typically, substances with the perovskite structure show lower symmetry, owing to the distortion of the crystal lattice and silicate perovskites are in the orthorhombic crystal system.[5]

Bridgmanite is a high-pressure polymorph of enstatite, but in the Earth predominantly forms, along with ferropericlase, from the decomposition of ringwoodite (a high-pressure form of olivine) at approximately 660 km depth, or a pressure of ~24 GPa.[5][6] The depth of this transition depends on the mantle temperature; it occurs slightly deeper in colder regions of the mantle and shallower in warmer regions.[7] The transition from ringwoodite to bridgmanite and ferropericlase marks the bottom of the mantle transition zone and the top of the lower mantle. Bridgmanite becomes unstable at a depth of approximately 2700 km, transforming isochemically to post-perovskite.[8]

Calcium silicate perovskite is stable at slightly shallower depths than bridgmanite, becoming stable at approximately 500 km, and remains stable throughout the lower mantle.[8]

Bridgmanite is the most abundant mineral in the mantle. The proportions of bridgmanite and calcium perovskite depends on the overall lithology and bulk composition. In pyrolitic and harzburgitic lithogies, bridgmanite constitutes around 80% of the mineral assemblage, and calcium perovskite < 10%. In an eclogitic lithology, bridgmanite and calcium perovskite comprise ~30% each.[8]

Calcium silicate perovskite has been identified at Earth's surface as inclusions in diamonds.[9] The diamonds are formed under high pressure deep in the mantle. With the great mechanical strength of the diamonds a large part of this pressure is retained inside the lattice, enabling inclusions such as the calcium silicate to be preserved in high-pressure form.

Experimental deformation of polycrystalline MgSiO
3
under the conditions of the uppermost part of the lower mantle suggests that silicate perovskite deforms by a dislocation creep mechanism. This may help explain the observed seismic anisotropy in the mantle.[10]

Cyclosilicates[edit | edit source]

Def. any group of silicates that have a ring of linked tetrahedra is called a cyclosilicate.

Abenakiite-(Ce)[edit | edit source]

Abenakiite-(Ce) is a cyclosilicate. Credit: Salah Rashad Zaqzoq.{{free media}}

Abenakiite-(Ce) has the chemical formula Na
26
Ce
6
(SiO
3
)
6
(PO
4
)
6
(CO
3
)
6
(S4+
O
2
)O
. Abenakiite-(Ce) (IMA1991-054; IMA Symbol Abk-Ce[11]) is a mineral of sodium, cerium, neodymium, lanthanum, praseodymium, thorium, samarium, oxygen, sulfur, carbon, phosphorus, and silicon. The silicate groups may be given as the cyclic Si
6
O
18
grouping. Its Mohs scale rating is 4 to 5.[12]

Abenakiite-(Ce) was discovered in a sodalite syenite xenolith at Mont Saint-Hilaire, Québec, Canada, together with aegirine, eudialyte, manganoneptunite, polylithionite, serandite, and steenstrupine-(Ce).[12][13]

Combination of elements in abenakiite-(Ce) is unique. Somewhat chemically similar mineral is steenstrupine-(Ce).[13][14] The hyper-sodium abenakiite-(Ce) is also unique in supposed presence of sulfur dioxide ligand. With a single grain (originally) found, abenakiite-(Ce) is extremely rare.[12]

In the crystal structure, described as a hexagonal net, of abenakiite-(Ce) there are:[12]

  • chains of NaO
    7
    polyhedra, connected with PO
    4
    groups
  • columns with six-membered rings of NaO
    7
    , and NaO
    7
    -REEO
    6
    , and SiO
    4
    polyhedra (REE - rare earth elements)
  • CO
    3
    groups, NaO
    6
    octahedra, and disordered SO
    2
    ligands within the columns

Alluaivites[edit | edit source]

Alluaivite (International Mineralogical Association (IMA) symbol: Aav[11]) is a rare mineral of the eudialyte group,[15] with complex formula written as Na
19
(Ca,Mn2+
)
6
(Ti,Nb)
3
Si
26
O
74
Cl
·2H
2
O
.[16][15] The two dual-nature minerals of the group, being both titano- and zirconosilicates, labyrinthite and dualite, respectively, contain the alluaivite module in their structures.[17][18] Alluaivite is named after Mt. Alluaiv in Lovozero Tundry massif, Kola Peninsula, Russia, where it is found in ultra-agpaitic, hyperalkaline pegmatites.[19][15][16]

Alluaivite contains relatively high amounts of admixing strontium, cerium, potassium, and barium, with lesser amounts of substituting lanthanum and zirconium.[19]

Alluaivite was found in ultra-agpaitic (highly alkaline) pegmatites on Mt. Alluaiv, Lovozero massif, Kola Peninsula, Russia - hence its name.[19] Associating minerals are aegirine, arfvedsonite, eudialyte, nepheline, potassic feldspar, and sodalite.[19]

Beryls[edit | edit source]

Colorless beryl, a cyclosilicate, is called goshenite. Credit: Piotr Menducki
Photograph is of a dioptase specimen from Renéville Republic of Congo. Credit: Didier Descouens.
Aquamarine is a blue or turquoise variety of beryl. Credit: .

"Beryl of various colors is found most commonly in granitic pegmatites, but also occurs in mica schists ... Goshenite [a beryl clear to white cyclosilicate] is found to some extent in almost all beryl localities."[20]

The gem-gravel placer deposits of Sri Lanka contain aquamarine.

The deep blue version of aquamarine is called maxixe. Maxixe is commonly found in the country of Madagascar. Its color fades to white when exposed to sunlight or is subjected to heat treatment, though the color returns with irradiation.

The pale blue color of aquamarine is attributed to Fe2+. The Fe3+ ions produce golden-yellow color, and when both Fe2+ and Fe3+ are present, the color is a darker blue as in maxixe. Decoloration of maxixe by light or heat thus may be due to the charge transfer Fe3+ and Fe2+.[21][22][23][24] Dark-blue maxixe color can be produced in green, pink or yellow beryl by irradiating it with high-energy particles (gamma rays, neutrons or even X-rays).[25]

Breyites[edit | edit source]

Breyite has the chemical formula Ca
3
Si
3
O
9
, crystallizes in the triclinic system, is a member of the margarosanite group of minerals, is a polymorph of pseudowollastonite and Wollastonite, and isostructural with margarosanite and walstromite.[26]

Breyite is a cyclosilicate.[27]

Eudialytes[edit | edit source]

Eudialyte is a somewhat rare, red silicate mineral. Credit: Baryonyx.

Eudialyte is a somewhat rare, red silicate mineral, which forms in alkaline igneous rocks, such as nepheline syenites.

Margarosanites[edit | edit source]

Walstromites[edit | edit source]

Inosilicates[edit | edit source]

Metasilicates[edit | edit source]

Def. the "oxyanion of silicon SiO32- or any salt or mineral containing this ion"[28] is called a metasilicate.

Pyroxferroites[edit | edit source]

These black crystals of pyroxferroite are from the famous Eifel quarry field, Bellerberg, Ettringen, Eifel Mountains, Germany. Credit: Giuseppe Siccardi.{{fairuse|permission:Giuseppe Siccardi}}

The pyroxferroite crystals in the image on the right are 0.6 x 1.1 x 0.7 cm in dimensions.

Raites[edit | edit source]

"This hydrated sodium-manganese silicate [raite] extends the already wide range of manganese crystal chemistry (3), which includes various complex oxides in ore deposits and nodules from the sea floor and certain farming areas, the pyroxmangite analog of the lunar volcanic metasilicate pyroxferroite, the Mn analog yofortierite of the clay mineral palygorskite, and the unnamed Mn analog of sepiolite."[29]

Wollastonites[edit | edit source]

Wollastonite is from the USGS and the Minerals Information Institute. Credit: Jeff Evarts.{{free media}}
White acicular crystals of wollastonite (field of view 8 mm) are from the Central Bohemia Region, Czech Republic. Credit: Leon Hupperichs.{{free media}}
Wollastonite skarn is with diopside (green), andradite garnet (red) and vesuvianite (dark brown) from the Stanisław mine near Szklarska Poręba, Izerskie Mountains, Lower Silesia, Poland. Credit: Piotr Sosnowski.{{free media}}
Unit cell is of triclinic wollastonite-1A. Credit: Solid State.{{free media}}
Tetrahedra arrangement within the chains in pyroxenes is compared to wollastonite. Credit: Solid State.{{free media}}

Wollastonite is a calcium metasilicate with the formula CaSiO
3
.

Wollastonite may contain small amounts of iron, magnesium, and manganese substituting for calcium that is usually white, forms when impure limestone or dolomite is subjected to high temperature and pressure, which sometimes occurs in the presence of silica-bearing fluids as in skarns,[30] or in contact with metamorphic rocks, named after the English chemist and mineralogist William Hyde Wollaston (1766–1828).

Despite its chemical similarity to the compositional spectrum of the pyroxene group of minerals—where magnesium and iron substitution for calcium ends with diopside and hedenbergite respectively—it is structurally very different, with a third SiO
4
tetrahedron[31] in the linked chain (as opposed to two in the pyroxenes).

In a pure CaSiO
3
, each component forms nearly half of the mineral by weight: 48.3% of CaO and 51.7% of SiO
2
. In some cases, small amounts of iron (Fe), and manganese (Mn), and lesser amounts of magnesium (Mg) substitute for calcium (Ca) in the mineral formula (e.g., rhodonit]).[32] Wollastonite can form a series of solid solutions in the system CaSiO
3
-FeSiO
3
, or hydrothermal synthesis of phases in the system MnSiO
3
-CaSiO
3
.[31]

Wollastonite usually occurs as a common constituent of a thermally metamorphosed impure limestone, it also could occur when the silicon is due to metamorphism in contact altered calcareous sediments, or to contamination in the invading igneous rock. In most of these occurrences it is the result of the following reaction between calcite and silica with the loss of carbon dioxide:[31]

CaCO3 + SiO2 → CaSiO3 + CO2

Wollastonite may also be produced in a diffusion reaction in skarn, it develops when limestone within a sandstone is metamorphosed by a dike, which results in the formation of wollastonite in the sandstone as a result of outward migration of Ca.[31]

Associated minerals: garnets, vesuvianite, diopside, tremolite, epidote, plagioclase feldspar, pyroxene and calcite. It is named after the English chemist and mineralogist William Hyde Wollaston (1766–1828).

Wollastonite crystallizes triclinically in space group P1 with the lattice constants a = 7.94 Å, b = 7.32 Å, c = 7.07 Å; α = 90,03°, β = 95,37°, γ = 103,43° and six formula units per unit cell.[33] Wollastonite was once classed structurally among the pyroxene group, because both of these groups have a ratio of Si:O = 1:3. In 1931, Warren and Biscoe showed that the crystal structure of wollastonite differs from minerals of the pyroxene group, and they classified this mineral within a group known as the pyroxenoids.[31] It has been shown that the pyroxenoid chains are more kinked than those of pyroxene group, and exhibit longer repeat distance. The structure of wollastonite contains infinite chains of [SiO
4
] tetrahedra sharing common vertices, running parallel to the b-axis. The chain motif in wollastonite repeats after three tetrahedra, whereas in pyroxenes only two are needed. The repeat distance in the wollastonite chains is 7.32 Å and equals the length of the crystallographic b-axis.

Molten CaSiO3, maintains a tetrahedral SiO4 local structure, at temperatures up to 2000 ˚C.[34] The nearest neighbour Ca-O coordination decreases from 6.0(2) in the room temperature glass to 5.0(2) in the 1700 ˚C liquid, coincident with an increasing number of longer Ca-O neighbors.[35][36]

"Primary silicate–melt and carbonate–salt inclusions occur in the phenocrysts (nepheline, fluorapatite, wollastonite, clinopyroxene) in the 1917 eruption combeite–wollastonite nephelinite at Oldoinyo Lengai."[37]

Large deposits of wollastonite have been identified in China, Finland, India, Mexico, and the United States. Smaller, but significant, deposits have been identified in Canada, Chile, Kenya, Namibia, South Africa, Spain, Sudan, Tajikistan, Turkey, and Uzbekistan.[38]

Nesosilicates[edit | edit source]

Orthosilicates[edit | edit source]

Phyllosilicates[edit | edit source]

Def. any "silicate mineral having a crystal structure of parallel sheets of silicate tetrahedra"[39] is called a phyllosilicate.

Ajoites[edit | edit source]

Bluish ajoite inclusion is in a colourless quartz crystal. Credit: Robert M. Lavinsky.{{free media}}
Ajoite is in quartz from Messina District, South Africa (size: 16.9 x 3.7 x 3 cm.) Credit: Robert M. Lavinsky.{{free media}}

Ajoite has the chemical formula (Na,K)Cu
7
AlSi
9
O
24
(OH)
6
·3H
2
O
,[40] and minor Mn, Fe and Ca are usually also present in the structure.[41] Ajoite is used as a minor ore of copper.

Ajoite (International Mineralogical Association (IMA) symbol Aj[11]) is a hydrated sodium potassium copper aluminium silicate hydroxide mineral.

Ajoite is a secondary mineral that forms from the oxidation of other secondary copper minerals in copper-rich base metal deposits in massive fracture coatings, in vein fillings, and in vugs. It may form from shattuckite and also it may be replaced by shattuckite.[41]

At the type locality it is associated with shattuckite, conichalcite, quartz, muscovite and pyrite.[42][40]

Ajoite is named after its type locality, the New Cornelia Mine in the Ajo District of Pima County, Arizona. Type specimen material is conserved at the National Museum of Natural History, Washington DC, USA, reference number 113220.

Other localities include Wickenburg and Maricopa County, Arizona, within the United States, and the Messina (Musina) District in South Africa. Quartz specimens from the defunct Messina Mines on the border between Zimbabwe and South Africa are well known for their inclusions of blue copper silicate minerals such as shattuckite, papagoite and ajoite,[43] but ajoite from American localities does not occur like this.

Biotites[edit | edit source]

Biotite is a black phyllosilicate mineral. Credit: United States Geological Survey and the Mineral Information Institute.

Biotite has the chemical formula "K(Mg, Fe)3(Al, Fe)Si3O10(OH, F)2".[44]

Def. a "dark brown mica; it is a mixed aluminosilicate and fluoride of potassium, magnesium and iron"[45] is called a biotite.

Garnierites[edit | edit source]

Garnierite is a general term for hydrous nickel silicates. Credit: Didier Descouens.{{free media}}

Chemical analysis of garnierite samples yields non-stoichiometric formulae that can be reduced to formulas like those of talc and serpentine suggesting a talc monohydrate formula of H
2
O
(Mg,Ni)
3
Si
4
O
10
(OH)
2
for the talc-like garnierite.[46]

The main difference between the serpentine-like and talc-like variants of garnierite is the spacing between layers in the structure, seen in x-ray powder diffraction studies. The serpentine-like variants have 7 Å basal spacings while the talc-like variants have a basal spacing of 10 Å.[46]

Garnierite is a layer silicate.[46]

7 Å type garnierites usually resemble chrysotile or lizardite in their structures, while 10 Å types usually resemble pimelite.[46]

The color comes from the presence of nickel in the mineral structure for magnesium.[46]

Kaolinites[edit | edit source]

Kaolin is a white phyllosilicate. Credit: USGS and the Minerals Information Institute.
Kaolinite is from Twiggs County, Georgia, USA. Credit: James St. John.{{free media}}

Kaolinite has the chemical formula Al
2
Si
2
O
5
(OH)
4
.

Kaolinite is a clay mineral, a layered silicate mineral, with one tetrahedral sheet of silica (SiO
4
) linked through oxygen atoms to one octahedral sheet of alumina (AlO
6
) octahedra.[31] Rocks that are rich in kaolinite are known as kaolin or porcelain (china) clay.[47]

The chemical formula for kaolinite as used in mineralogy is Al
2
Si
2
O
5
(OH)
4
,[48] however, in ceramics applications the formula is typically written in terms of oxides, thus the formula for kaolinite is Al
2
O
3
*2SiO
2
*2H
2
O
.[49]

As the most numerous element is oxygen at 9 for 52.9 at %, kaolin is an oxide.

Micas[edit | edit source]

Here is mica in a rock. Credit: Rpervinking.{{free media}}

Def. a group of monoclinic phyllosilicates with the general formula[50]

X2Y4–6Z8O20(OH,F)4
in which X is K, Na, or Ca or less commonly Ba, Rb, or Cs;
Y is Al, Mg, or Fe or less commonly Mn, Cr, Ti, Li, etc.;
Z is chiefly Si or Al, but also may include Fe3+ or Ti;
dioctahedral (Y = 4) and trioctahedral (Y = 6)

is called a mica.

Muscovites[edit | edit source]

The Nikon image shows discrete flakes of muscovite. Credit: Luis Miguel Bugallo Sánchez.{{free media}}

Def. a "pale brown mineral of the mica group, being a basic potassium aluminosilicate[51] with the chemical formula KAl2(Si3Al)O10(OH],F)2"[52] is called a muscovite.

"The strongly peraluminous tuffs contain phenocrysts of andalusite, sillimanite, and muscovite and have high 87Sr/86Sri (0.7258 and 0.7226) and δ18O (+11‰). Elevated concentrations of Li, Cs, Be, Sn, B, and other minor elements compare with those in “tin granites.”"[53]

Serpentines[edit | edit source]

Serpentine is from Poland. Credit: Kluka.{{free media}}
A sample of serpentinite rock is partially made up of chrysotile, from Slovakia. Credit: Helix84.{{free media}}
A rock of serpentinite is from the Maurienne valley, Savoie, French Alps. Credit: Gabriel HM.{{free media}}
Sample of serpentinite from the Golden Gate National Recreation Area, California, United States. Credit: Zimbres|Eurico Zimbres.{{free media}}
Chromitic serpentinite (7.9 cm (3.1 in) across), Styria Province, Austria. Protolith was a Proterozoic-Early Paleozoic upper mantle dunite peridotite that has been multiply metamorphosed during the Devonian, Permian, and Mesozoic. Credit: James St. John.{{free media}}
Tightly folded serpentinite is from the Tux Alps, Austria, closeup view about 30 cm × 20 cm (11.8 in × 7.9 in). Credit: Hermann Hammer.{{free media}}

The serpentine subgroup (part of the kaolinite-serpentine group)[54] are greenish, brownish, or spotted minerals commonly found in serpentinite rocks, used as a source of magnesium and asbestos, and as a decorative stone.[55] The name is thought to come from the greenish color being that of a serpent.[56]

The serpentine subgroup are a set of common rock-forming hydroxyl magnesium iron phyllosilicates (Mg,Fe)
3
Si
2
O
5
(OH)
4
minerals, resulting from the metamorphism of the minerals that are contained in ultramafic rocks.[57] They may contain minor amounts of other elements including chromium, manganese, cobalt or nickel. In mineralogy and gemology, serpentine may refer to any of 20 varieties belonging to the serpentine subgroup. Owing to admixture, these varieties are not always easy to individualize, and distinctions are not usually made. There are three important mineral polymorphs of serpentine: antigorite, chrysotile and lizardite.

The serpentine subgroup of minerals are polymorphous, meaning that they have the same chemical formulae, but the atoms are arranged into different structures, or crystal lattices.[58] Chrysotile, which has a fiberous habit, is one polymorph of serpentine and is one of the more important asbestos minerals. Other polymorphs in the serpentine subgroup may have a platy habit. Antigorite and lizardite are the polymorphs with platy habit.

Serpentinization is a form of low-temperature metamorphism of ultramafic rocks, such as dunite, harzburgite, or lherzolite. These are rocks low in silica and composed mostly of olivine, pyroxene, and chromite. Serpentinization is driven largely by hydration and oxidation of olivine and pyroxene to serpentine minerals, brucite, and magnetite.[59] Under the unusual chemical conditions accompanying serpentinization, water is the oxidizing agent, and is itself reduced to hydrogen, H
2
. This leads to further reactions that produce rare iron group native element minerals, such as awaruite (Ni
3
Fe
) and native iron;[60] methane and other hydrocarbon compounds; and hydrogen sulfide.[61]

During serpentinization, large amounts of water are absorbed into the rock, increasing the volume, reducing the density and destroying the original structure.[62][63] The density changes from 3.3 to 2.5 g/cm3 (0.119 to 0.090 lb/cu in) with a concurrent volume increase on the order of 30-40%.[64] The reaction is highly exothermic and rock temperatures can be raised by about 260 °C (500 °F),[63] providing an energy source for formation of non-volcanic hydrothermal vents.[65] The hydrogen, methane, and hydrogen sulfide produced during serpentinization are released at these vents and provide energy sources for deep sea chemotroph microorganisms.[66][63]

The final mineral composition of serpentinite is usually dominated by lizardite, chrysotile, and magnetite. Brucite and antigorite are less commonly present. Lizardite, chrysotile, and antigorite are serpentine minerals. Accessory minerals, present in small quantities, include awaruite, other native metal minerals, and sulfide minerals.[67]

Olivine is a solid solution of forsterite, the magnesium-endmember, and fayalite, the iron-endmember, with forsterite typically making up about 90% of the olivine in ultramafic rocks.[68] Serpentinite can form from olivine via several reactions:

Forsterite3 Mg
2
SiO
4
+ silicon dioxideSiO
2
+ 4 H
2
O
serpentine2 Mg
3
Si
2
O
5
(OH)
4

 

 

 

 

(Reaction 1a)

Forsterite2 Mg
2
SiO
4
+ water3 H
2
O
serpentineMg
3
Si
2
O
5
(OH)
4
+ bruciteMg(OH)
2

 

 

 

 

(Reaction 1b)

Reaction 1a tightly binds silica, lowering its chemical activity to the lowest values seen in common rocks of the Earth's crust.[69] Serpentinization then continues through the hydration of olivine to yield serpentine and brucite (Reaction 1b).[70] The mixture of brucite and serpentine formed by Reaction 1b has the lowest silica activity in the serpentinite, so that the brucite phase is very important in understanding serpentinization.[69] However, the brucite is often blended in with the serpentine such that it is difficult to identify except with X-ray diffraction, and it is easily altered under surface weathering conditions.[71]

A similar suite of reactions involves pyroxene-group minerals:

Enstatite3 MgSiO
3
+ silicon dioxideSiO
2
+ H
2
O
talcMg
3
Si
4
O
10
(OH)
2

 

 

 

 

(Reaction 2a)

Enstatite6 MgSiO
3
+ 3 H
2
O
serpentineMg
3
Si
2
O
5
(OH)
4
+ talcMg
3
Si
4
O
10
(OH)
2

 

 

 

 

(Reaction 2b)

Reaction 2a quickly comes to a halt as silica becomes unavailable, and Reaction 2b takes over.[72] When olivine is abundant, silica activity drops low enough that talc begins to react with olivine:

Forsterite6 Mg
2
SiO
4
+ talcMg
3
Si
4
O
10
(OH)
2
+ water9 H
2
O
serpentine5 Mg
3
Si
2
O
5
(OH)
4

 

 

 

 

(Reaction 3)

This reaction requires higher temperatures than those at which brucite forms.[73]

The final mineralogy depends both on rock and fluid compositions, temperature, and pressure. Antigorite forms in reactions at temperatures that can exceed 600 °C (1,112 °F) during metamorphism, and it is the serpentine group mineral stable at the highest temperatures. Lizardite and chrysotile can form at low temperatures very near the Earth's surface.[74]

Ultramafic rocks often contain calcium-rich pyroxene (diopside), which breaks down according to the reaction

Diopside3 CaMgSi
2
O
6
+ 6 H+
serpentineMg
3
Si
2
O
5
(OH)
4
+ 3 Ca2+
+ H
2
O
+ silicon dioxide4 SiO
2

 

 

 

 

(Reaction 4)

This raises both the pH, often to very high values, and the calcium content of the fluids involved in serpentinization. These fluids are highly reactive and may transport calcium and other elements into surrounding mafic rocks. Fluid reaction with these rocks may create metasomatic reaction zones enriched in calcium and depleted in silica, called rodingites.[75]

In most crustal rock, the chemical activity of oxygen is prevented from dropping to very low values by the fayalite-magnetite-quartz (FMQ) buffer.[76] The very low chemical activity of silica during serpentinization eliminates this buffer, allowing serpentinization to produce highly reducing conditions.[69] Under these conditions, water is capable of oxidizing ferrous (Fe2+
) ions in fayalite. The process is of interest because it generates hydrogen gas:[77][78]

Fayalite3 Fe
2
SiO
4
+ water2 H
2
O
magnetite2 Fe
3
O
4
+ silicon dioxide3 SiO
2
+ hydrogen2 H
2

 

 

 

 

(Reaction 5)

However, studies of serpentinites suggest that iron minerals are first converted to ferroan brucite, Fe(OH)
2
,[79] which then undergoes the Schikorr reaction in the anaerobic conditions of serpentinization:[80][81]

6 Fe(OH)
2
ferrous hydroxide
2 Fe
3
O
4
magnetite
+ 4 H
2
O
water
+ 2 H
2
hydrogen

 

 

 

 

(Reaction 6)

Maximum reducing conditions, and the maximum rate of production of hydrogen, occur when the temperature of serpentinization is between 200 and 315 °C (392 and 599 °F).[82] If the original ultramafic rock (the protolith) is peridotite, which is rich in olivine, considerable magnetite and hydrogen are produced. When the protolith is pyroxenite, which contains more pyroxene than olivine, iron-rich talc is produced with no magnetite and only modest hydrogen production. Infiltration of silica-bearing fluids during serpentinization can suppress both the formation of brucite and the subsequent production of hydrogen.[83]

Chromite present in the protolith will be altered to chromium-rich magnetite at lower serpentinization temperatures. At higher temperatures, it will be altered to iron-rich chromite (ferrit-chromite).[84] During serpentinization, the rock is enriched in chlorine, boron, fluorine, and sulfur. Sulfur will be reduce to hydrogen sulfide and sulfide minerals, though significant quantities are incorporated into serpentine minerals, and some may later be reoxidized to sulfate minerals such as anhydrite.[64] The sulfides produced include nickel-rich sulfides, such as mackinawite.[85]

Laboratory experiments have confirmed that at a temperature of 300 °C (572 °F) and pressure of 500 bars, olivine serpentinizes with release of hydrogen gas. In addition, methane and complex hydrocarbons are formed through reduction of carbon dioxide. The process may be catalyzed by magnetite formed during serpentinization.[61] One reaction pathway is:[80]

forsterite18 Mg
2
SiO
4
+ fayalite6 Fe
2
SiO
4
+ 26 H
2
O
+ CO
2
serpentine12 Mg
3
Si
2
O
5
(OH)
4
+ magnetite4 Fe
3
O
4
+ methaneCH
4

 

 

 

 

(Reaction 7)

Lizardite and chrysotile are stable at low temperatures and pressures, while antigorite is stable at higher temperatures and pressure. Its presence in a serpentinite indicates either that serpentinization took place at unusually high pressure and temperature or that the rock experienced higher grade metamorphism after serpentinization was complete.[86]

Infiltration of CO
2
-bearing fluids into serpentinite causes distinctive talc-carbonate alteration. Brucite rapidly converts to magnesite and serpentine minerals (other than antigorite) are converted to talc. The presence of pseudomorphs of the original serpentinite minerals shows that this alteration takes place after serpentinization.[87]

Serpentinite may contain chlorite, tremolite, and metamorphic olivine and diopside. This indicates that the serpentinite has been subject to more intense metamorphism, reaching the upper greenschist or amphibolite metamorphic facies.[88]

Above about 450 °C (842 °F), antigorite begins to break down. Thus serpentinite does not exist at higher metamorphic facies.[66]

Sorosilicates[edit | edit source]

Tectosilicates[edit | edit source]

Def. any "of various silicate minerals ... with a three-dimensional framework of silicate tetrahedra"[89] is called a tectosilicate.

Def. type "of silicate crystal structure characterized by the sharing of all SiO4 tetrahedral oxygens resulting in three-dimensional framework structures"[44] is called a tektosilicate.

Quartzes[edit | edit source]

This is a sample from a hydrothermal quartz (white)-gold vein (Precambrian) of the Archean Cadillac Group in southwestern Quebec, Canada. Credit: James St. John.{{free media}}

Red "thermoluminescence (RTL) emission from quartz, as a dosimeter for baked sediments and volcanic deposits, [from] older (i.e., >1 Ma), quartz-bearing known age volcanic deposits [can use as standards] independently-dated silicic volcanic deposits from New Zealand, ranging in age from 300 ka through to 1.6 Ma."[90]

Alpha quartzes[edit | edit source]

This image shows a piece of alpha quartz with many crystals. Credit: Basham Jewelry.{{fairuse}}
The photomicrographs show of a sand grain held in an amorphous matrix, in plane-polarized light on top, cross-polarized light on bottom. Scale box in mm. Credit: Qfl247.
This is a thin section with cross-polarized right through a sand-sized quartz grain of 0.13 mm diameter. Credit: Glen A. Izett, USGS.
This is a thin section of a shocked quartz grain. Credit: Martin Schmieder.

Def. "a continuous framework [tectosilicate] of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall [chemical] formula [of] SiO2 ... [of] trigonal trapezohedral class 3 2"[91], usually with some substitutional or interstitial impurities, is called α-quartz.

Alpha-quartz (space group P3121, no. 152, or P3221, no. 154) under a high pressure of 2-3 gigapascals and a moderately high temperature of 700°C changes space group to monoclinic C2/c, no. 15, and becomes the mineral coesite. It is "found in extreme conditions such as the impact craters of meteorites.

When the concentration of interstitial or substitutional impurities becomes sufficient to change the space group of a mineral such as α-quartz, the result is another mineral. When the physical conditions are sufficient to change the solid space group of α-quartz without changing the chemical composition or formula, another mineral results.

Referring to the image on the right: "Lake County experienced incredible volcanic activity. The heat melted the quartz but temperatures and pressures were just right so it was not destroyed. Rather, the melted quartz was carried along with the lava flows."[92]

"Shocked quartz is associated with two high pressure polymorphs of silicon dioxide: coesite and stishovite. These polymorphs have a crystal structure different from standard quartz. Again, this structure can only be formed by intense pressure, but moderate temperatures. High temperatures would anneal the quartz back to its standard form."[93]

"Short-lived bottle-green or blue luminescence colours with zones of non-luminescing bands are very common in authigenic quartz overgrowths, fracture fillings or idiomorphic vein crystals. Dark brown, short-lived yellow or pink colours are often found in quartz replacing sulphate minerals. Quartz from tectonically active regions commonly exhibits a brown luminescence colour. A red luminescence colour is typical for quartz crystallized close to a volcanic dyke or sill."[94]

So far several of the polymorphs of α-quartz formed at high temperature and pressure occur with rock types away from meteorite impact craters.

At lower right is a thin section through a sand-sized quartz grain "from the USGS-NASA Langley core showing two well-developed, intersecting sets of shock lamellae produced by the late Eocene Chesapeake Bay bolide impact. This shocked quartz grain is from the upper part of the crater-fill deposits at a depth of 820.6 ft in the core. The corehole is located at the NASA Langley Research Center, Hampton, VA, near the southwestern margin of the Chesapeake Bay impact crater."[95] "Very high pressures produced by strong shock waves cause dislocations in the crystal structure of quartz grains along preferred orientations. These dislocations appear as sets of parallel lamellae in the quartz when viewed with a petrographic microscope. Bolide impacts are the only natural process known to produce shock lamellae in quartz grains."[95]

At third down on the right shows another thin section in plane polarized light of a shocked quartz grain with two sets of decorated planar deformation features (PDFs) surrounded by a cryptocrystalline matrix from the Suvasvesi South impact structure, Finland.

In a specimen of shocked quartz, stishovite can be separated from quartz by applying hydrogen fluoride (HF); unlike quartz, stishovite will not react.[96]

The major evidence for a volcanic origin for tektites "includes: close analogy between shaped tektites and small volcanic bombs, and between layered tektites and lava or tuff-lava flows or huge bombs; analogy between flanged tektites and volcanic bombs ablated by gasjets: long-time, multistage formation of some tektites that corresponds to wide variations in their radiometric ages; well-ordered long compositional trends (series) typical of magmatic differentiation; different compositional tektite families (subseries) comparable to different stages (phases) of the volcanic process."[97]

"As with the North American microtektite-bearing cores, all the Australasian microtektite-bearing cores containing coesite and shocked quartz also contained volcanic ash, which complicated the search."[98]

Beta quartzes[edit | edit source]

Beta quartz (β-Quartz) is stable "between 573° and 870°C".[44]

Coesites[edit | edit source]

Crossed-polars image of coesite grain (gray) ~1 mm across is in eclogite, small colored inclusion is pyroxene, polycrystalline rim is quartz. Credit: J. Smyth.{{free media}}
Atomic structure is of coesite. Credit: Materialscientist.{{free media}}

Coesite is a polymorph of silicon dioxide SiO
2
that is formed when very high pressure (2–3 gigapascals), and moderately high temperature (700 °C, 1,300 °F), are applied to quartz. Coesite was first synthesized by Loring Coes Jr., a chemist at the Norton Company, in 1953.[99][100]

In 1960, a natural occurrence of coesite was reported by Edward C. T. Chao,[101] in collaboration with Eugene Shoemaker, from the Barringer Crater, in Arizona, US, which was evidence that the crater must have been formed by an impact. After this report, the presence of coesite in unmetamorphosed rocks was taken as evidence of a meteorite impact event or of an atomic bomb explosion. It was not expected that coesite would survive in high pressure metamorphic rocks.

In metamorphic rocks, coesite was initially described in eclogite xenoliths from the mantle of the Earth that were carried up by ascending magmas; kimberlite is the most common host of such xenoliths.[102] In metamorphic rocks, coesite is now recognized as one of the best mineral indicators of metamorphism at very high pressures (UHP, or ultrahigh-pressure metamorphism).[103] Such UHP metamorphic rocks record subduction or continental collisions in which crustal rocks are carried to depths of 70 km (43 mi) or more. Coesite is formed at pressures above about 2.5 GPa (25 kbar) and temperature above about 700 °C. This corresponds to a depth of about 70 km in the Earth. It can be preserved as mineral inclusions in other phases because as it partially reverts to quartz, the quartz rim exerts pressure on the core of the grain, preserving the metastable grain as tectonic forces uplift and expose these rock at the surface. As a result, the grains have a characteristic texture of a polycrystalline quartz rim.

Coesite has been identified in UHP metamorphic rocks around the world, including the western Alps of Italy at Dora Maira,[103] the Erzgebirge of Germany,[104] the Lanterman Range of Antarctica,[105] in the Kokchetav Massif of Kazakhstan,[106] in the Western Gneiss region of Norway,[107] the Dabie-Shan Range in Eastern China,[108] the Himalayas of Eastern Pakistan,[109] and the Vermont Appalachian Mountains.[110][111]

Coesite is a tectosilicate with each silicon atom surrounded by four oxygen atoms in a tetrahedron. Each oxygen atom is then bonded to two Si atoms to form a framework. There are two crystallographically distinct Si atoms and five different oxygen positions in the unit cell. Although the unit cell is close to being hexagonal in shape ("a" and "c" are nearly equal and β nearly 120°), it is inherently monoclinic and cannot be hexagonal. The crystal structure of coesite is similar to that of feldspar and consists of four silicon dioxide tetrahedra arranged in Si
4
O
8
and Si
8
O
16
rings. The rings are further arranged into chains. This structure is metastable within the stability field of quartz: coesite will eventually decay back into quartz with a consequent volume increase, although the metamorphic reaction is very slow at the low temperatures of the Earth's surface. The crystal symmetry is monoclinic C2/c, No.15, Pearson symbol mS48.[112]

Cristobalites[edit | edit source]

Cristobalite spheres appear within obsidian. Credit: Rob Lavinsky.{{free media}}

Def. a high-temperature (above 1470°C) polymorph of α-quartz with cubic, Fd3m, space group no. 227, and a tetragonal form (P41212, space group no. 92) is called cristobalite.

Def. a "mineral of volcanic rocks that solidified at a high temperature [...] chemically identical to quartz, with the chemical formula SiO2, but has a different crystal structure"[113] is called cristobalite.

There is more than one form of the cristobalite framework. At high temperatures, the structure is called β-cristobalite. It is in the cubic crystal system, space group Fd3m (No. 227, Pearson symbol cF104).[114] It has the diamond structure but with linked tetrahedra of silicon and oxygen where the carbon atoms are in diamond. A chiral tetragonal form called α-cristobalite (space group either P41212, No. 92,[115] or P43212, No. 96, at random) occurs on cooling below about 250 °C at ambient pressure and is related to the cubic form by static tilting of the silica tetrahedra in the framework. This transition is variously called the low-high or transition. It may be termed "displacive"; i.e., it is not generally possible to prevent the cubic β-form from becoming tetragonal by rapid cooling. Under rare circumstances the cubic form may be preserved if the crystal grain is pinned in a matrix that does not allow for the considerable spontaneous strain that is involved in the transition, which causes a change in shape of the crystal. This transition is highly discontinuous. Going from the α form to the β form causes an increase in volume of 3[116] or 4[117] percent. The exact transition temperature depends on the crystallinity of the cristobalite sample, which itself depends on factors such as how long it has been annealed at a particular temperature.

The cubic β phase consists of dynamically disordered silica tetrahedra. The tetrahedra remain fairly regular and are displaced from their ideal static orientations due to the action of a class of low-frequency phonons called rigid unit modes. It is the "freezing" of one of these rigid unit modes that is the soft mode for the α–β transition.

In β-cristobalite, there are right-handed and left-handed helices of tetrahedra (or of silicon atoms) parallel to all three axes. But in the α–β phase transition, only the right-handed or the left-handed helix in one direction is preserved (the other becoming a two-fold screw axis), so only one of the three degenerate cubic crystallographic axes retains a fourfold rotational axis (actually a screw axis) in the tetragonal form. (That axis becomes the "c" axis, and the new "a" axes are rotated 45° compared to the other two old axes. The new "a" lattice parameter is shorter by approximately the square root of 2, so the α unit cell contains only 4 silicon atoms rather than 8.) The choice of axis is arbitrary, so that various twins can form within the same grain. These different twin orientations coupled with the discontinuous nature of the transition (volume and slight shape change) can cause considerable mechanical damage to materials in which cristobalite is present and that pass repeatedly through the transition temperature, such as refractory bricks.

When devitrifying silica, cristobalite is usually the first phase to form, even when well outside its thermodynamic stability range. This is an example of Ostwald's step rule. The dynamically disordered nature of the β-phase is partly responsible for the low enthalpy of fusion of silica.

The micrometre-scale spheres that make up precious opal exhibit some x-ray diffraction patterns that are similar to that of cristobalite, but lack any long-range order so they are not considered true cristobalite. In addition, the presence of structural water in opal makes it doubtful that opal consists of cristobalite.[118][119]

Stishovites[edit | edit source]

Crystal structure is of stishovite. Credit: Materialscientist.{{free media}}

Stishovite is an extremely hard, dense tetragonal polymorph of silicon dioxide. It is very rare on the Earth's surface; however, it may be a predominant form of silicon dioxide in the Earth, especially in the lower mantle.[120]

Stishovite was named after Sergey M. Stishov, a Russian high-pressure physicist who first synthesized the mineral in 1961. It was discovered in Meteor Crater in 1962 by Edward C. T. Chao.[121]

Unlike other silica polymorphs, the crystal structure of stishovite resembles that of rutile TiO
2
. The silicon in stishovite adopts an octahedral coordination geometry, being bound to six oxides. Similarly, the oxides are three-connected, unlike low-pressure forms of SiO2. In most silicates, silicon is tetrahedral, being bound to four oxides.[122] It was long considered the hardest known oxide (~30 GPa Vickers[123]); however, boron suboxide has been discovered[124] in 2002 to be much harder. At normal temperature and pressure, stishovite is metastable.

Stishovite can be separated from quartz by applying hydrogen fluoride (HF); unlike quartz, stishovite will not react.[121]

Large natural crystals of stishovite are extremely rare and are usually found as clasts of 1 to 2 mm in length. When found, they can be difficult to distinguish from regular quartz without laboratory analysis. It has a vitreous luster, is transparent (or translucent), and is extremely hard. Stishovite usually sits as small rounded gravels in a matrix of other minerals.

Until recently, the only known occurrences of stishovite in nature formed at the very high shock pressures (>100 kbar, or 10 GPa) and temperatures (> 1200 °C) present during hypervelocity meteorite impact into quartz-bearing rock. Minute amounts of stishovite have been found within diamonds,[125] and post-stishovite phases were identified within ultra-high-pressure mantle rocks.[126] Stishovite may also be synthesized by duplicating these conditions in the laboratory, either isostatically or through shock (see shocked quartz).[127] At 4.287 g/cm3, it is the second densest polymorph of silica, after seifertite. It has tetragonal crystal symmetry, P42/mnm, No. 136, Pearson symbol tP6.[128]

Def. a polymorph of α-quartz formed by pressures > 100 kbar or 10 GPa and temperatures > 1200 °C is called stishovite.[129]

Stishovite may be formed by an instantaneous over pressure such as by an impact or nuclear explosion type event.[93]

Minute amounts of stishovite has been found within diamonds.[125]

Tridymites[edit | edit source]

Tabular tridymite crystals are from Ochtendung, Eifel, Germany. Credit: Fred Kruijen.{{free media}}
Specimen consists of "porcelainite" - a semivitrified chert- or jasper-like rock composed of cordierite, mullite and tridymite, admixture of corundum, and subordinate K-feldspar. Credit: John Krygier.{{free media}}
Crystal structure is of α-tridymite. Credit: Andel.{{free media}}
Crystal structure is of β-tridymite. Credit: Andel.{{free media}}

Def. a polymorph of α-quartz formed at temperatures from 22-460°C with at least seven space groups for its forms with tabular crystals is called tridymite.[130]

Def. a "rare [tektosilicate] mineral of volcanic rocks that solidified at a high temperature, [with the chemical composition of silicon dioxide, SiO22,] chemically identical to quartz, but has a different crystal structure"[131] is called a tridymite.

Tridymite is a high-temperature polymorph of silica and usually occurs as minute tabular white or colorless pseudo-hexagonal crystals, or scales, in cavities in felsic volcanic rocks. Its chemical formula is SiO
2
. Tridymite was first described in 1868 and the type location is in Hidalgo, Mexico. The name is from the Greek tridymos for triplet as tridymite commonly occurs as twinned crystal trillings[132] (compound crystals comprising three twinned crystal components).

α-tridymite is orthorhomic and β-tridymite is hexagonal.[44]

Tridymite can occur in seven crystalline forms. Two of the most common at standard pressure are known as α and β. The α-tridymite phase is favored at elevated temperatures (>870 °C) and it converts to β-cristobalite at 1470 °C.[133][31] However, tridymite does usually not form from pure β-quartz, one needs to add trace amounts of certain compounds to achieve this.[134] Otherwise the β-quartz-tridymite transition is skipped and β-quartz transitions directly to cristobalite at 1050 °C without occurrence of the tridymite phase.

Crystal phases of tridymite[31]
Name Symmetry Space group T (°C)
HP (β) Hexagonal P63/mmc 460
LHP Hexagonal P6322 400
OC (α) Orthorhombic C2221 220
OS Orthorhombic 100–200
OP Orthorhombic P212121 155
MC Monoclinic Cc 22
MX Monoclinic C1 22

In the table, M, O, H, C, P, L and S stand for monoclinic, orthorhombic, hexagonal, centered, primitive, low (temperature) and superlattice. T indicates the temperature, at which the corresponding phase is relatively stable, though the interconversions between phases are complex and sample dependent, and all these forms can coexist at ambient conditions.[135] Mineralogy handbooks often arbitrarily assign tridymite to the triclinic crystal system, yet use hexagonal Miller indices because of the hexagonal crystal shape (see infobox image).[132]

Feldspars[edit | edit source]

This feldspar crystal is stark white showing excellent symmetry with appropriate faces. Credit: Robert M. Lavinsky.{{free media}}
Porphyritic rhyolite with euhedral feldspars indicates two phases of cooling: one slow, one fast, size: 12 cm. Credit: Stephen Hui.{{fairuse}}
This is a naturally occurring collection of intergrown feldspar crystals. Credit: Dave Dyet.{{fairuse}}

Def. a group of "aluminum silicates [aluminosilicates] of the alkali metals sodium, potassium, calcium and barium"[136] are called feldspars, or feldspar.

"Feldspar is by far the most abundant group of minerals in the earth's crust, forming about 60% of terrestrial rocks."[137]

"The mineralogical composition of most feldspars can be expressed in terms of the ternary system Orthoclase (KAlSi3O8), Albite (NaAlSi3O8) and Anorthite (CaAl2Si2O8)."[137]

"The minerals of which the composition is comprised between Albite and Anorthite are known as the plagioclase feldspars, while those comprised between Albite and Orthoclase are called the alkali feldspars due to the presence of alkali metals sodium and potassium."[137]

Albites[edit | edit source]

Albite crystals are from Crete. Credit: Rock Currier.{{free media}}

Albite (International Mineralogical Association (IMA) symbol: Ab[11]) is a plagioclase feldspar mineral, is the sodium endmember of the plagioclase solid solution series, represents a plagioclase with less than 10% anorthite content. The pure albite endmember has the formula NaAlSi
3
O
8
, a tectosilicate, is usually pure white, hence its name from Latin, albus,[138] and is a common constituent in felsic rocks. The almost end member has the chemical formula Na
(1.0-0.9)
Ca
(0.0-0.1)
Al
(1.0-1.1)
Si
(3.0-2.9)
O
8
.[139]

There are two variants of albite, which are referred to as 'low albite' and 'high albite'; the latter is also known as 'analbite'. Although both variants are triclinic, they differ in the volume of their unit cell, which is slightly larger for the 'high' form. The 'high' form can be produced from the 'low' form by heating above 750 °C (1,380 °F)[140] High albite can be found in meteor impact craters such as in Winslow, Coconino Co., Arizona, United States.[141] Upon further heating to more than 1,050 °C (1,920 °F) the crystal symmetry changes from triclinic to monoclinic; this variant is also known as 'monalbite'.[142] Albite melts at 1,100–1,120 °C (2,010–2,050 °F).[143]

Albites occur in granitic and pegmatite masses (often as the variety Cleavelandite),[144] in some hydrothermal vein deposits, and forms part of the typical greenschist metamorphic facies for rocks of originally basaltic composition. Minerals that albite is often considered associated with in occurrence include biotite, hornblende, orthoclase, muscovite and quartz.[145]

Occurrence: "A major constituent of granites and granite pegmatites, alkalic diorites, basalts, and in hydrothermal and alpine veins. A product of potassium metasomatism and in low-temperature and low-pressure metamorphic facies and in some schists. Detrital and authigenic in sedimentary rocks."[139]

Polymorphs: Kumdykolite, Lingunite.[145]

Structural modifications: "Low- and high-temperature structural modifications exist ('low albite' and 'high albite'), with ordered and disordered Al-Si distribution, respectively."[145]

"The Na-rich end member of the Albite-Anorthite Series (= Plagioclase)."[145]

Empirical formula: Na
0.95
Ca
0.05
Al
1.05
Si
2.95
O
8
.[146]

Anorthites[edit | edit source]

Anorthite crystals are in a basalt vug from Vesuvius. Credit: Robert M. Lavinsky.{{free media}}

Anorthites have the chemical formula CaAl
2
Si
2
O
8
.[147]

Anorthite is rare on the Earth[50] but abundant on the Moon.[148]

Anorthite is a rare compositional variety of plagioclase that occurs in mafic igneous rock, also occurs in metamorphic rocks of granulite facies, in metamorphosed carbonate rocks, and corundum deposits,[149] type localities are Monte Somma and Valle di Fassa, Italy. It was first described in 1823,[150] more rare in surficial rocks than it normally would be due to its high weathering potential in the Goldich dissolution series.

It also makes up much of the lunar highlands; the Genesis Rock, collected during the 1971 Apollo 15 mission, is made of anorthosite, a rock composed largely of anorthite. Anorthite was discovered in samples from comet Wild 2, and the mineral is an important constituent of Ca-Al-rich inclusions in rare varieties of chondritic meteorites.

Anorthoclases[edit | edit source]

When potassium replaces the sodium characteristic in albite at amounts of up to 10%, the mineral is then considered to be anorthoclase.[151]

Oligoclases[edit | edit source]

Oligoclase is from Chihuahua, Mexico. Credit: Rob Lavinsky.{{free media}}

"The apical parts of large volcanoes along the East Pacific Rise (islands and seamounts) are encrusted with rocks of the alkali volcanic suite (alkali basalt, andesine- and oligoclase-andesite, and trachyte)."[152]

Orthoclases[edit | edit source]

This is a perfect, simple, tan orthoclase crystal from Penticton in British Columbia. Credit: Robert Lavinsky.{{free media}}

"The mineralogical composition of most feldspars can be expressed in terms of the ternary system Orthoclase (KAlSi3O8), Albite (NaAlSi3O8) and Anorthite (CaAl2Si2O8)."[137]

"The minerals of which the composition is comprised between Albite and Anorthite are known as the plagioclase feldspars, while those comprised between Albite and Orthoclase are called the alkali feldspars due to the presence of alkali metals sodium and potassium."[137]

"Volcanic rock fragments, feldspar (orthoclase, andesine, and rare sanidine), and small amounts of quartz, biotite, and hornblende make up the bulk of these rocks."[153]

Plagioclases[edit | edit source]

Brown and white, light to average, aphanitic porpheritic phenocrysts of sodic plagioclase 50-60 % with a ground mass of the same at 10-15 %. Credit: Kevin T.{{fairuse}}

Def. "[a]ny of a group of aluminum silicate feldspathic minerals ranging in their ratio of calcium to sodium"[154] is called plagioclase.

Plagioclase is a series of tectosilicate minerals within the feldspar group with a specific chemical composition: NaAlSi
3
O
8
CaAl
2
Si
2
O
8
. Plagioclase in hand samples is often identified by its polysynthetic crystal twinning or 'record-groove' effect.

Plagioclase minerals and their compositions
Name % CaAl2Si2O8
% NaAlSi3O8 Image
Anorthite 90–100 10–0
Bytownite 70–90 30–10
Labradorite 50–70 50–30
Andesine 30–50 70–50
Oligoclase 10–30 90–70
Albite 0–10 100–90

Feldspathoids[edit | edit source]

Def. any of a group of silicates "that did not contain enough silica to satisfy all the chemical bonds"[155] of the framework is called a feldspathoid.

Volcanic sources that have a low silica concentration are more likely to produce feldspathoid-containing rocks than feldspar-containing rocks.

Feldspathoid volcanic rocks occur in "a suite of basanites, olivine nephelinites, and olivine melilite nephelinites from the Raton-Clayton volcanic field, New Mexico."[156]

"Volcanism in the Raton-Clayton field commenced approximately 7.5 Ma ago with the eruption of alkali basalts and continued intermittently until at least 10,000 y.a. with the eruption of the Capulin Mountain silicic alkalic basalt (Stormer 1972a; Baldwin and Muehlberger 1959). The entire volcanic sequence was erupted onto the high plains east of the Sangre de Cristo Mountains, and as such, represents the eastern limit of late Cenozoic volcanism in the western U.S. Volcanic activity in the Raton-Clayton field was contemporaneous with volcanism in the Rio Grande rift, and the Raton-Clayton volcanic field is interpreted as part of the Rio Grande rift system."[156]

Kalsilites[edit | edit source]

Sharp pale tan prismatic hexagonal crystals of the mineral kalsilite, from: Löhley, Üdersdorf, Eifel, Rhineland-Palatinate, Germany. Credit: David Hospital.{{free media}}
Kaliophilite exhibited in the Southern Vermont Natural History Museum, Marlboro, Vermont, USA. Credit: Daderot.{{free media}}
Kaliophilite from Monte Somma, Somma-Vesuvius Complex, Naples Province, Campania, Italy. Credit: Leon Hupperichs.{{free media}}

Def. "a rare mineral, a form of KAlSiO4, found in volcanic rocks in parts of Italy"[157] is called a kaliophilite.

Kalsilite (KAlSiO
4
) is a vitreous white to grey feldspathoid that is found in some potassium-rich lavas, such as from Chamengo Crater in Uganda that has a relative Mohs hardness of 5.5.

"Kaliophilite [occurs in] blocks of biotite-pyroxenite volcanic ejecta from Mte. Somma, Vesuvius."[158]

Nephelines[edit | edit source]

Nepheline crystal is from Canaã alkaline massif, Rio de Janeiro. Credit: Zimbres.{{free media}}
This is a mineral specimen of nepheline (white) with small black inclusions. Credit: Andrew Silver, USGS.{{free media}}

Def. a (Na,K)AlSiO4 "feldspathoid mineral of silica-poor igneous, plutonic and volcanic rocks"[159] is called a nepheline.

Quadridavynes[edit | edit source]

The image shows light colored crystals of Quadridavyne from Mt Vesuvius, Somma-Vesuvius Complex, Naples Province, Campania, Italy. Credit: Hudson Institute of Mineralogy.{{fairuse}}

Def. a feldspathoid, tektosilicate "mineral found in volcanic ash"[160], chemical formula Na6Ca2Si6Al6O24Cl4, is called a quadridavyne.

Quadridavyne is a tektosilicate (feldspathoid), chemical formula Na6Ca2Si6Al6O24Cl4, with a type locality of Ottaviano, Monte Somma, Somma-Vesuvius Complex, Naples Province, Campania, Italy.[161]

Zeolites[edit | edit source]

A combination specimen of four zeolite species. The radiating natrolite crystals are protected in a pocket with associated stilbite. The matrix around and above the pocket is lined with small, pink-colored laumontite crystals. Heulandite is also present as a crystal cluster on the backside. Credit: Rob Lavinsky.{{free media}}

The zeolite structural group (Nickel-Strunz classification) includes:[162][163][164][165][166]

  • 09.GA. - Zeolites with T5O10 units (T = combined Si and Al) – the fibrous zeolites
    • Natrolite framework (NAT): gonnardite, natrolite, mesolite, paranatrolite, scolecite, tetranatrolite
    • Edingtonite framework (EDI): edingtonite, kalborsite
    • Thomsonite framework (THO): thomsonite-series
  • 09.GB. - Chains of single connected 4-membered rings
    • Analcime framework (ANA): analcime, leucite, pollucite, wairakite
    • Laumontite (LAU), yugawaralite (YUG), goosecreekite (GOO), montesommaite (MON)
  • 09.GC. - Chains of doubly connected 4-membered rings
    • Phillipsite framework (PHI): harmotome, phillipsite-series
    • Gismondine framework (GIS): amicite, gismondine, garronite, gobbinsite
    • Boggsite (BOG), merlinoite (MER), mazzite-series (MAZ), paulingite-series (PAU), perlialite (Linde type L framework, zeolite L, LTL)
  • 09.GD. - Chains of 6-membered rings – tabular zeolites
    • Chabazite framework (CHA): chabazite-series, herschelite, willhendersonite and SSZ-13
    • Faujasite framework (FAU): faujasite-series, Linde type X (zeolite X, X zeolites), Linde type Y (zeolite Y, Y zeolites)
    • Mordenite framework (MOR): maricopaite, mordenite
    • Offretite–wenkite subgroup 09.GD.25 (Nickel–Strunz, 10 ed): offretite (OFF), wenkite (WEN)
    • Bellbergite (TMA-E, Aiello and Barrer; framework type EAB), bikitaite (BIK), erionite-series (ERI), ferrierite (FER), gmelinite (GME), levyne-series (LEV), dachiardite-series (DAC), epistilbite (EPI)
  • 09.GE. - Chains of T10O20 tetrahedra (T = combined Si and Al)
    • Heulandite framework (HEU): clinoptilolite, heulandite-series
    • Stilbite framework (STI): barrerite, stellerite, stilbite-series
    • Brewsterite framework (BRE): brewsterite-series
  • Others
    • Cowlesite, pentasil (also known as ZSM-5, framework type MFI), tschernichite (beta polymorph A, disordered framework, BEA), Linde type A framework (zeolite A, LTA)

Analcites[edit | edit source]

Colorless sharply formed undamaged crystals of analcime to 25 mm in diameter on a 78 mm x 65 mm x 53 mm matrix. Credit: Carles Millan.

The image on the right contains analcime, or analcite, as colorless sharply formed undamaged crystals to 25 mm in diameter on a 78 mm x 65 mm x 53 mm matrix. They are associated with numerous black prismatic terminated crystals of aegirine, as well as smaller colorless prismatic terminated crystals of natrolite, these from 3 mm to 10 mm in length. Aegirine is a pyroxene. Natrolite is another feldspathoid like analcime of the zeolite group.

Def. a "mineral, a sodium aluminosilicate [with a chemical formula NaAlSi2O6·H2O,][167] having a zeolite structure, found in alkaline basalts"[168] is called an analcime.

Barrerites[edit | edit source]

Barrerite is a rare zeolite species related to stilbite, but found in just a few localities and not nearly as common. Credit: Rob Lavinsky.{{free media}}

Barrerite can have the chemical formula Na4Al4Si14O36•13(H2O).[169]

"Ca may be calcium and/or potassium."[170] Barrerite can have the chemical formula K4Al4Si14O36•13(H2O).[170]

Def. a "white to pinkish tectosilicate zeolite mineral"[171] is called a barrerite.

Leucites[edit | edit source]

Leucite, here a trapezohedral crystal, is a relatively rare feldspathoid. Credit: Rob Lavinsky.{{free media}}

Def. a feldspathoid "mineral of silica-poor igneous, plutonic and volcanic rocks"[172] is called a leucite.

Natrolites[edit | edit source]

Natrolite crystals in a cavity of a volcanic rock. Credit: G.dallorto.{{free media}}

Natrolite is another feldspathoid like analcime of the zeolite group.

"Occurs chiefly in cavities in basalt".[44]

Def. a "fibrous zeolite mineral, being a sodium aluminosilicate,[173] of the chemical formula Na2Al2Si3O10·2H2O"[174] is called a natrolite.

Stellerites[edit | edit source]

A very fine Australian zeolite mineral with lustrous stellerite bowties of deep salmon color. Credit: Rob Lavinsky.{{free media}}

Stellerite has the chemical formula CaAl2Si7O18•7(H2O).[175]

Def. a "hydrated calcium aluminosilicate zeolite, similar to stilbite"[176] is called a stellerite.

Stilbites[edit | edit source]

Photograph shows a stilbite specimen from Kiui Island, Alaska, USA. Credit: Dlloyd.{{fairuse}}

Stilbite (Desmine), a zeolite group, has the chemical formula NaCa2Al5Si13O36•16(H2O).[44]

Def. a "tectosilicate zeolite mineral consisting of hydrated calcium aluminium silicate, common in volcanic rocks"[177] is called a stilbite.

Stilbite-Na can have the chemical formula Na3Ca3Al8Si28O72•30(H2O).[178]

Stilbite-Ca can have the chemical formula NaCa4Al8Si28O72•30(H2O).[179]

Hypotheses[edit | edit source]

  1. Most minerals on Earth are oxides.

See also[edit | edit source]

References[edit | edit source]

  1. 1.0 1.1 "Bridgmanite".
  2. Tomioka, Naotaka; Fujino, Kiyoshi (22 August 1997). "Natural (Mg,Fe)SiO
    3
    -Ilmenite and -Perovskite in the Tenham Meteorite". Science 277 (5329): 1084–1086. doi:10.1126/science.277.5329.1084. PMID 9262473.
     
  3. Tschauner, Oliver; Ma, Chi; Beckett, John R.; Prescher, Clemens; Prakapenka, Vitali B.; Rossman, George R. (27 November 2014). "Discovery of bridgmanite, the most abundant mineral in Earth, in a shocked meteorite". Science 346 (6213): 1100–1102. doi:10.1126/science.1259369. PMID 25430766. https://authors.library.caltech.edu/52186/1/Tschauner.SM.pdf. 
  4. Wendel, JoAnna (10 June 2014). "Mineral Named After Nobel Physicist". Eos, Transactions American Geophysical Union 95 (23): 195. doi:10.1002/2014EO230005. 
  5. 5.0 5.1 Hemley, R.J.; Cohen R.E. (1992). "Silicate Perovskite". Annual Review of Earth and Planetary Sciences 20: 553–600. doi:10.1146/annurev.ea.20.050192.003005. 
  6. Agee, Carl B. (1998). "Phase transformations and seismic structure in the upper mantle and transition zone". In Hemley, Russell J. Ultrahigh Pressure Mineralogy. pp. 165–204. doi:10.1515/9781501509179-007. ISBN 978-1-5015-0917-9. 
  7. Flanagan, Megan P.; Shearer, Peter M. (10 February 1998). "Global mapping of topography on transition zone velocity discontinuities by stacking precursors". Journal of Geophysical Research: Solid Earth 103 (B2): 2673–2692. doi:10.1029/97JB03212. 
  8. 8.0 8.1 8.2 Stixrude (:0), Lars; Lithgow-Bertelloni, Carolina (30 May 2012). "Geophysics of Chemical Heterogeneity in the Mantle". Annual Review of Earth and Planetary Sciences 40 (1): 569–595. doi:10.1146/annurev.earth.36.031207.124244. 
  9. Nestola, F.; Korolev, N.; Kopylova, M.; Rotiroti, N.; Pearson, D. G.; Pamato, M. G.; Alvaro, M.; Peruzzo, L. et al. (March 2018). "CaSiO
    3
    perovskite in diamond indicates the recycling of oceanic crust into the lower mantle"
    . Nature 555 (7695): 237–241. doi:10.1038/nature25972. PMID 29516998. https://discovery.ucl.ac.uk/id/eprint/10049984/1/Nature_accepted.pdf.
     
  10. Cordier, Patrick; Ungár, Tamás; Zsoldos, Lehel; Tichy, Géza (April 2004). "Dislocation creep in MgSiO
    3
    perovskite at conditions of the Earth's uppermost lower mantle". Nature 428 (6985): 837–840. doi:10.1038/nature02472. PMID 15103372.
     
  11. 11.0 11.1 11.2 11.3 Warr, L.N. (2021). "IMA-CNMNC approved mineral symbols". Mineralogical Magazine 85: 291-320. https://www.cambridge.org/core/journals/mineralogical-magazine/article/imacnmnc-approved-mineral-symbols/62311F45ED37831D78603C6E6B25EE0A. 
  12. 12.0 12.1 12.2 12.3 McDonald, A.M., Chao, G.Y., and Grice, J.D., 1994. Abenakiite-(Ce), a new silicophosphate carbonate mineral from Mont Saint-Hilaire, Quebec: Description and structure determination. The Canadian Mineralogist 32, 843-854
  13. 13.0 13.1 Mindat, Abenakiite-(Ce), Mindat.org
  14. "[International Mineralogical Association] : List of Minerals - IMA". Ima-mineralogy.org. Retrieved 2016-03-12.
  15. 15.0 15.1 15.2 http://www.mindat.org/show.php?id=141&ld=2 Mindat
  16. 16.0 16.1 Khomyakov A. P., Netschelyustov G. N. and Rastsvetaeva R. K. 1990: Alluaivite Na
    19
    (Ca,Mn)
    6
    (Ti,Nb)
    3
    Si
    26
    O
    74
    Cl
    ·2H
    2
    O
    - A new titanosilicate mineral of eudialyte-like structure. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva, 119(3), 117-120, in Jambor J. L. and Puziewicz J. 1991: New mineral names. American Mineralogist, 76, 1728-1735; [1]
  17. Khomyakov, A.P., Nechelyustov, G.N., and Rastsvetaeva, R.K., 2006. Labyrinthite (Na,K,Sr)
    35
    Ca
    12
    Fe
    3
    Zr
    6
    TiSi
    51
    O
    144
    (O,OH,H
    2
    O
    )
    9
    Cl
    3
    , a new mineral with a modular eudialyte-like structure from Khibiny Alkaline Massif, Kola Peninsula, Russia. Zapiski Vserossiyskogo Mineralogicheskogo Obshchestva 135(2), 38-49
  18. Khomyakov, A.P., Nechelyustov, G.N., and Rastsvetaeva, R.K., 2009: Dualite, Na
    30
    (Ca,Na,Ce,Sr)
    12
    (Na,Mn,Fe,Ti)
    6
    Zr
    3
    Ti
    3
    MnSi
    51
    O
    144
    (OH,H
    2
    O
    ,Cl)
    9
    , a new zircono-titanosilicate with a modular eudialyte-like structure from the Lovozero alkaline Pluton, Kola Peninsula, Russia. Geology of Ore Deposits 50(7), 574-582
  19. 19.0 19.1 19.2 19.3 http://www.handbookofmineralogy.org/pdfs/Alluaivite.PDF Handbook of Mineralogy
  20. "Beryl". San Francisco, California: Wikimedia Foundation, Inc. April 15, 2013. Retrieved 2013-05-03.
  21. Color in the Beryl group. http://minerals.caltech.edu/ImageS/Visible/BERYL/Index.htm. Retrieved 2009-06-06. 
  22. Ibragimova, E. M.; Mukhamedshina, N. M.; Islamov, A. Kh. (2009). "Correlations between admixtures and color centers created upon irradiation of natural beryl crystals". Inorganic Materials 45 (2): 162. doi:10.1134/S0020168509020101. 
  23. R. R. Viana; G. M. Da Costa; E. De Grave; W. B. Stern; H. Jordt-Evangelista. "Characterization of beryl (aquamarine variety) by Mössbauer spectroscopy 2002". Physics and Chemistry of Minerals 29: 78. doi:10.1007/s002690100210. 
  24. Ana Regina Blak; Sadao Isotani; Shigueo Watanabe. "Optical absorption and electron spin resonance in blue and green natural beryl: A reply 1983". Physics and Chemistry of Minerals 9 (6): 279. doi:10.1007/BF00309581. 
  25. K. Nassau (1976). "The deep blue Maxixe-type color center in beryl". American Mineralogist 61: 100. http://www.minsocam.org/ammin/AM61/AM61_100.pdf. 
  26. F.E. Brenker (2021). "Breyite". Mindat.org. Retrieved 23 November 2021.
  27. F.E. Brenker (2021). "Breyite". Mindat.org. Retrieved 23 November 2021.
  28. "metasilicate". San Francisco, California: Wikimedia Foundation, Inc. June 20, 2013. Retrieved 2013-09-02.
  29. Joseph J. Pluth; Joseph V. Smith; Dmitry Y. Pushcharovsky; Eugenii I. Semenov; Andreas Bram; Christian Riekel; Hans-Peter Weber; Robert W. Broach (11 November 1997). "Third-generation synchrotron x-ray diffraction of 6-μm crystal of raite, ≈Na3Mn3Ti0.25Si8O20(OH)2⋅10H2O, opens up new chemistry and physics of low-temperature minerals". Proceedings of the National Academy of Sciences of the United States of America 94 (23): 12263–12267. http://www.pnas.org/content/94/23/12263.full. Retrieved 2017-02-22. 
  30. Whitley, Sean; Halama, Ralf; Gertisser, Ralf; Preece, Katie; Deegan, Frances M.; Troll, Valentin R. (2020-10-18). "Magmatic and Metasomatic Effects of Magma–Carbonate Interaction Recorded in Calc-silicate Xenoliths from Merapi Volcano (Indonesia)". Journal of Petrology 61 (4). doi:10.1093/petrology/egaa048. ISSN 0022-3530. https://academic.oup.com/petrology/article/61/4/egaa048/5822871. 
  31. 31.0 31.1 31.2 31.3 31.4 31.5 31.6 31.7 William Alexander Deer; Robert Andrew Howie; J. Zussman (1992). An introduction to the rock-forming minerals. Longman Scientific & Technical. ISBN 978-0-470-21809-9. 
  32. Andrews, R. W. Wollastonite. London, Her Majesty's Stationery Office, 1970.
  33. Buerger, M. J. (1961). "The crystal structures of wollastonite and pectolite". Proceedings of the National Academy of Sciences 47 (12): 1884–1888. doi:10.1073/pnas.47.12.1884. PMID 16578516. PMC 223235. //www.ncbi.nlm.nih.gov/pmc/articles/PMC223235/. 
  34. Benmore, C.J. (2010). "Temperature-dependent structural heterogeneity in calcium silicate liquids". Physical Review B 82 (22): 224202. doi:10.1103/PhysRevB.82.224202. https://digital.library.unt.edu/ark:/67531/metadc107770/. 
  35. Skinner, L.B. (2012). "Structure of Molten CaSiO3: Neutron Diffraction Isotope Substitution with Aerodynamic Levitation and Molecular Dynamics Study". J. Phys. Chem. B 116 (45): 13439–13447. doi:10.1021/jp3066019. PMID 23106223. 
  36. Eckersley, M.C. (1988). "Structural ordering in a calcium silicate glass". Nature 355 (6190): 525–527. doi:10.1038/335525a0. 
  37. Victor V. Sharygina; Vadim S. Kamenetsky; Anatoly N. Zaitsev; Maya B. Kamenetsky (1 November 2012). "Silicate–natrocarbonatite liquid immiscibility in 1917 eruption combeite–wollastonite nephelinite, Oldoinyo Lengai Volcano, Tanzania: Melt inclusion study". Lithos 152: 23-39. doi:10.1016/j.lithos.2012.01.021. https://www.researchgate.net/profile/Victor_Sharygin/publication/255712999_Silicatenatrocarbonatite_liquid_immiscibility_in_1917_eruption_combeitewollastonite_nephelinite_Oldoinyo_Lengai_Volcano_Tanzania_Melt_inclusion_study/links/02e7e5205ca0996b2c000000.pdf. Retrieved 2017-02-20. 
  38. Wollastonite, USGS Mineral Commodity Summaries 2017
  39. "phyllosilicate". San Francisco, California: Wikimedia Foundation, Inc. June 17, 2013. Retrieved 2013-09-02.
  40. 40.0 40.1 Ajoite. Handbook of Mineralogy. Retrieved on 2011-10-09.
  41. 41.0 41.1 Gaines, et al (1997) Dana's New Mineralogy, Eighth Edition. Wiley
  42. Ajoite. Mindat.org (2011-08-16). Retrieved on 2011-10-09.
  43. Bruce Cairncross (2004). Field guide to rocks & minerals of Southern Africa. Struik. p. 172. ISBN 978-1-86872-985-2. https://books.google.com/books?id=7yJkQkWROvoC. Retrieved 9 October 2011. 
  44. 44.0 44.1 44.2 44.3 44.4 44.5 Willard Lincoln Roberts; George Robert Rapp Jr.; Julius Weber (1974). Encyclopedia of Minerals. New York, New York, USA: Van Nostrand Reinhold Company. pp. 693. ISBN 0-442-26820-3. 
  45. SemperBlotto (27 February 2007). "biotite, In: Wiktionary". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-22. {{cite web}}: |author= has generic name (help)
  46. 46.0 46.1 46.2 46.3 46.4 Brindley, G.W. and Hang, P.T. (1973) The nature of garnierites – I Structures, chemical compositions and color characteristics. Clays and Clay Minerals, 21, 27-40.
  47. Pohl, Walter L. (2011). Economic geology: principles and practice: metals, minerals, coal and hydrocarbons – introduction to formation and sustainable exploitation of mineral deposits. Chichester, West Sussex: Wiley-Blackwell. pp. 331. ISBN 9781444336627. https://books.google.com/books?id=Jq2rpN-6AccC. 
  48. Anthony JW, Bideaux RA, Bladh KW, Nichols MC, ed (1995). Kaolinite, In: Handbook of Mineralogy: Silica, silicates. Tucson, Arizona, USA: Mineral Data Publishing. ISBN 9780962209734. OCLC 928816381. http://www.handbookofmineralogy.org/pdfs/kaolinite.pdf. 
  49. Perry DL (2011). Handbook of Inorganic Compounds (2nd ed.). Boca Raton: Taylor & Francis. ISBN 9781439814611. OCLC 587104373. 
  50. 50.0 50.1 Deer, W. A., R. A. Howie and J. Zussman (1966) An Introduction to the Rock Forming Minerals, Longman, ISBN 0-582-44210-9
  51. SemperBlotto (22 April 2006). "muscovite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-22. {{cite web}}: |author= has generic name (help)
  52. Rhanyeia (6 April 2008). "muscovite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-22. {{cite web}}: |author= has generic name (help)
  53. Donald C. Noble; Thomas A. Vogel; Paula S. Peterson; Gary P. Landis; Norman K. Grant; Peter A. Jezek; Edwin H. McKee (January 1984). "Rare-element–enriched, S-type ash-flow tuffs containing phenocrysts of muscovite, andalusite, and sillimanite, southeastern Peru". Geology 12 (1): 35-9. doi:10.1130/0091-7613(1984)​12<35:RSATCP>​2.0.CO;2. http://geology.gsapubs.org/content/12/1/35.short. Retrieved 2017-02-19. 
  54. "Serpentine Subgroup". mindat.org. Retrieved 30 April 2021.
  55. Serpentine, American Heritage Dictionary
  56. Rudler, Frederick William (1911). "Serpentine" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. 24 (11th ed.). Cambridge University Press. pp. 675–677.
  57. "Serpentine definition in the Dictionary of Geology". Retrieved 9 July 2018.
  58. "Serpentine: The mineral Serpentine information and pictures". www.minerals.net. Retrieved 4 April 2018.
  59. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos 9 (2): 125–138. doi:10.1016/0024-4937(76)90030-X. 
  60. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  61. 61.0 61.1 Berndt, Michael E.; Allen, Douglas E.; Seyfried, William E. (1 April 1996). "Reduction of CO2 during serpentinization of olivine at 300 °C and 500 bar". Geology 24 (4): 351–354. doi:10.1130/0091-7613(1996)024<0351:ROCDSO>2.3.CO;2. 
  62. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  63. 63.0 63.1 63.2 Serpentinization: The heat engine at Lost City and sponge of the oceanic crust
  64. 64.0 64.1 Mével, Catherine (September 2003). "Serpentinization of abyssal peridotites at mid-ocean ridges". Comptes Rendus Geoscience 335 (10–11): 825–852. doi:10.1016/j.crte.2003.08.006. 
  65. Lowell, R. P. (2002). "Seafloor hydrothermal systems driven by the serpentinization of peridotite". Geophysical Research Letters 29 (11): 1531. doi:10.1029/2001GL014411. 
  66. 66.0 66.1 Früh-Green, Gretchen L.; Connolly, James A.D.; Plas, Alessio; Kelley, Deborah S.; Grobéty, Bernard (2004). "Serpentinization of oceanic peridotites: Implications for geochemical cycles and biological activity". Geophysical Monograph Series 144: 119–136. doi:10.1029/144GM08. ISBN 0-87590-409-2. 
  67. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  68. Snow, Jonathan E.; Dick, Henry J.B. (October 1995). "Pervasive magnesium loss by marine weathering of peridotite". Geochimica et Cosmochimica Acta 59 (20): 4219–4235. doi:10.1016/0016-7037(95)00239-V. 
  69. 69.0 69.1 69.2 Frost, B. R.; Beard, J. S. (3 April 2007). "On Silica Activity and Serpentinization". Journal of Petrology 48 (7): 1351–1368. doi:10.1093/petrology/egm021. 
  70. Coleman, Robert G. (1977). Ophiolites. Springer-Verlag. pp. 100–101. ISBN 978-3540082767. 
  71. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  72. Frost, B. R.; Beard, J. S. (3 April 2007). "On Silica Activity and Serpentinization". Journal of Petrology. 48 (7): 1351–1368. doi:10.1093/petrology/egm021.
  73. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  74. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  75. Frost, B. R.; Beard, J. S. (3 April 2007). "On Silica Activity and Serpentinization". Journal of Petrology. 48 (7): 1351–1368. doi:10.1093/petrology/egm021.
  76. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  77. "Methane and hydrogen formation from rocks – Energy sources for life". Retrieved 2011-11-06.
  78. Sleep, N.H.; A. Meibom, Th. Fridriksson, R.G. Coleman, D.K. Bird (2004). "H2-rich fluids from serpentinization: Geochemical and biotic implications". Proceedings of the National Academy of Sciences of the United States of America 101 (35): 12818–12823. doi:10.1073/pnas.0405289101. PMID 15326313. PMC 516479. //www.ncbi.nlm.nih.gov/pmc/articles/PMC516479/. 
  79. Bach, Wolfgang; Paulick, Holger; Garrido, Carlos J.; Ildefonse, Benoit; Meurer, William P.; Humphris, Susan E. (2006). "Unraveling the sequence of serpentinization reactions: petrography, mineral chemistry, and petrophysics of serpentinites from MAR 15°N (ODP Leg 209, Site 1274)". Geophysical Research Letters 33 (13): L13306. doi:10.1029/2006GL025681. 
  80. 80.0 80.1 Russell, M. J.; Hall, A. J.; Martin, W. (2010). "Serpentinization as a source of energy at the origin of life". Geobiology 8 (5): 355–371. doi:10.1111/j.1472-4669.2010.00249.x. PMID 20572872. 
  81. Schrenk, M. O.; Brazelton, W. J.; Lang, S. Q. (2013). "Serpentinization, Carbon, and Deep Life". Reviews in Mineralogy and Geochemistry 75 (1): 575–606. doi:10.2138/rmg.2013.75.18. 
  82. McCollom, Thomas M.; Bach, Wolfgang (February 2009). "Thermodynamic constraints on hydrogen generation during serpentinization of ultramafic rocks". Geochimica et Cosmochimica Acta 73 (3): 856–875. doi:10.1016/j.gca.2008.10.032. 
  83. Klein, Frieder; Bach, Wolfgang; McCollom, Thomas M. (September 2013). "Compositional controls on hydrogen generation during serpentinization of ultramafic rocks". Lithos 178: 55–69. doi:10.1016/j.lithos.2013.03.008. 
  84. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  85. Delacour, Adélie; Früh-Green, Gretchen L.; Bernasconi, Stefano M. (October 2008). "Sulfur mineralogy and geochemistry of serpentinites and gabbros of the Atlantis Massif (IODP Site U1309)". Geochimica et Cosmochimica Acta 72 (20): 5111–5127. doi:10.1016/j.gca.2008.07.018. 
  86. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  87. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  88. Moody, Judith B. (April 1976). "Serpentinization: a review". Lithos. 9 (2): 125–138. Bibcode:1976Litho...9..125M. doi:10.1016/0024-4937(76)90030-X.
  89. "tectosilicate". San Francisco, California: Wikimedia Foundation, Inc. June 17, 2013. Retrieved 2013-09-02.
  90. M. Fattahi; S. Stokes (December 2000). "Extending the time range of luminescence dating using red TL (RTL) from volcanic quartz". Radiation Measurements 32 (5-6): 479-85. doi:10.1016/S1350-4487(00)00105-0. http://www.sciencedirect.com/science/article/pii/S1350448700001050. Retrieved 2016-02-12. 
  91. "Quartz". San Francisco, California: Wikimedia Foundation, Inc. October 22, 2012. Retrieved 2012-10-23.
  92. Basham Jewelry (2006). "Lake County Diamonds". Lake County, California USA: FreeWebs.com. Retrieved 2016-02-12.
  93. 93.0 93.1 "Shocked quartz". San Francisco, California: Wikimedia Foundation, Inc. May 14, 2012. Retrieved 2012-10-23.
  94. K. Ramseyer; J. Baumann; A. Matter; J. Mullis (December 1988). "Cathodoluminescence Colours of α-Quartz". Mineralogical Magazine 52 (368): 669-77. doi:10.1180/minmag.1988.052.368.11. http://www.minersoc.org/pages/Archive-MM/Volume_52/52-368-669.htm. Retrieved 2016-02-12. 
  95. 95.0 95.1 Glen A. Izett (September 26, 2000). "Shocked Quartz from the USGS -- NASA Langley Core". U. S. Geological Survey. Retrieved 2012-10-23.
  96. Michael Fleischer (1962). "New mineral names" (PDF). American Mineralogist (Mineralogical Society of America) 47 (2): 172–4. http://rruff.info/uploads/AM47_805.pdf. 
  97. EP Izokh (1996). "Origin of tektites: an alternative to terrestrial impact theory". Chemie der Erde : Beitrage zur Chemischen Mineralogie, Petrographie und Geologie 56: 458-74. PMID 11541098. http://ukpmc.ac.uk/abstract/MED/11541098. Retrieved 2012-10-23. 
  98. B. P. Glass; Jiquan Wu (May 1993). "Coesite and shocked quartz discovered in the, Australasian and North American, microtektite layers". Geology 21 (5): 435-8. doi:10.1130/0091-7613(1993)021<0435:CASQDI>2.3.CO;2. http://geology.geoscienceworld.org/content/21/5/435.short. Retrieved 2012-10-23. 
  99. The word "coesite" is pronounced as "Coze-ite" after chemist Loring Coes Jr. Coes, L. Jr. (31 July 1953). "A New Dense Crystalline Silica". Science 118 (3057): 131–132. doi:10.1126/science.118.3057.131. PMID 17835139. 
  100. Robert M. Hazen (22 July 1999). The Diamond Makers. Cambridge University Press. pp. 91–. ISBN 978-0-521-65474-6. https://books.google.com/books?id=fNJQok6N9_MC&pg=PA91. Retrieved 6 June 2012. 
  101. Chao, E. C. T.; Shoemaker, E. M.; Madsen, B. M. (1960). "First Natural Occurrence of Coesite". Science 132 (3421): 220–2. doi:10.1126/science.132.3421.220. PMID 17748937. 
  102. Smyth, Joseph R.; Hatton, C.J. (1977). "A coesite-sanidine grospydite from the Roberts Victor kimberlite". Earth and Planetary Science Letters 34 (2): 284. doi:10.1016/0012-821X(77)90012-7. 
  103. 103.0 103.1 Chopin, Christian (1984). "Coesite and pure pyrope in high-grade blueschists of the Western Alps: a first record and some consequences". Contributions to Mineralogy and Petrology 86 (2): 107–118. doi:10.1007/BF00381838. 
  104. Massonne, H.-J. (2001). "First find of coesite in the ultrahigh-pressure metamorphic area of the central Erzgebirge, Germany". European Journal of Mineralogy 13 (3): 565–570. doi:10.1127/0935-1221/2001/0013-0565. 
  105. Ghiribelli, B.; Frezzotti, M.L.; Palmeri, R. (2002). "Coesite in eclogites of the Lanterman Range (Antarctica): Evidence from textural and Raman studies". European Journal of Mineralogy 14 (2): 355–360. doi:10.1127/0935-1221/2002/0014-0355. 
  106. Korsakov, A.V.; Shatskiy, V. S.; Sobolev N.V. (1998). "Первая находка коэсита в эклогитах Кокчетавского массива (First occurrence of coesite in eclogites from the Kokchetav Massif)". Doklady Earth Sciences 359: 77–81. 
  107. Smith, D.C. (1984). "Coesite in clinopyroxene in the Caledonides and its implications for geodynamics". Nature 310 (5979): 641–644. doi:10.1038/310641a0. 
  108. Schertl, H.-P.; Okay, A.I. (1994). "A coesite inclusion in dolomite in Dabie Shan, China: petrological and rheological significance". Eur. J. Mineral. 6 (6): 995–1000. doi:10.1127/ejm/6/6/0995. http://eurjmin.geoscienceworld.org/content/6/6/995.short. 
  109. O'Brien, P.J., N. Zotov, R. Law, M.A. Khan and M.Q. Jan (2001). "Coesite in Himalayan eclogite and implications for models of India-Asia collision". Geology 29 (5): 435–438. doi:10.1130/0091-7613(2001)029<0435:CIHEAI>2.0.CO;2. 
  110. Joseph Gonzalez, Suzanne Baldwin, Jay B Thomas, William O Nachlas, Paul G Fitzgerald (2019). "First Discovery of Coesite in the Appalachians: Characterization of Prograde Metamorphism in a Taconic Metapelite". AGU Fall Meeting 2019: V51B–03. https://agu.confex.com/agu/fm19/meetingapp.cgi/Paper/552005. 
  111. Joseph Gonzalez, Suzanne Baldwin, Jay B Thomas, William O Nachlas, Paul G Fitzgerald (2020). "Evidence for ultrahigh-pressure metamorphism discovered in the Appalachian orogen". Geology. doi:10.1130/G47507.1. 
  112. Levien L.; Prewitt C.T. (1981). "High-pressure crystal structure and compressibility of coesite". American Mineralogist 66: 324–333. Archived on 2016-06-04. Error: If you specify |archivedate=, you must also specify |archiveurl=. https://web.archive.org/web/20160604062422/http://www.minsocam.org/ammin/AM66/AM66_324.pdf. Retrieved 2009-12-15. 
  113. Pinkfud (8 November 2004). "cristobalite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-20. {{cite web}}: |author= has generic name (help)
  114. Wright A. F., Leadbetter A. J. (1975). "The structures of the b-cristobalite phases of SiO2 and AlPO4". Philosophical Magazine 31 (6): 1391–1401. doi:10.1080/00318087508228690. 
  115. Downs R. T., Palmer D. C. (1994). "The pressure behavior of a cristobalite". American Mineralogist 79: 9–14. Archived on 2019-05-15. Error: If you specify |archivedate=, you must also specify |archiveurl=. https://web.archive.org/web/20190515215339/https://www.geo.arizona.edu/xtal/group/pdf/AM79_9.pdf. Retrieved 2009-12-15. 
  116. R.E. Smallman & R.J. Bishop (1999). "2". Modern Physical Metallurgy and Materials Engineering (6 ed.). ISBN 978-0-7506-4564-5. https://www.sciencedirect.com/topics/engineering/cristobalite. 
  117. A.J. Leadbetter & A.F. Wright (1976). "The α—β transition in the cristobalite phases of SiO2 and AIPO4 I. X-ray studies". The Philosophical Magazine. doi:10.1080/14786437608221095. 
  118. Deane K. Smith (1998). "Opal, cristobalite, and tridymite: Noncrystallinity versus crystallinity, nomenclature of the silica minerals and bibliography". Powder Diffraction 13 (1): 2–19. doi:10.1017/S0885715600009696. http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=8512817. 
  119. "Nomenclature of the Forms of Crystalline and Non-Crystalline Silica" (PDF). 2016-03-04.
  120. Dmitry L. Lakshtanov "The post-stishovite phase transition in hydrous alumina-bearing SiO
    2
    in the lower mantle of the earth" PNAS 2007 104 (34) 13588-13590; doi:10.1073/pnas.0706113104.
  121. 121.0 121.1 Fleischer, Michael (1962). "New mineral names". American Mineralogist (Mineralogical Society of America) 47 (2): 172–174. http://rruff.info/uploads/AM47_805.pdf. 
  122. Ross, Nancy L. (1990). "High pressure crystal chemistry of stishovite". American Mineralogist (Mineralogical Society of America) 75 (7): 739–747. http://www.minsocam.org/ammin/AM75/AM75_739.pdf. 
  123. Luo, Sheng-Nian; Swadener, J. G.; Ma, Chi; Tschauner, Oliver (2007). "Examining crystallographic orientation dependence of hardness of silica stishovite". Physica B: Condensed Matter 399 (2): 138. doi:10.1016/j.physb.2007.06.011. http://www.its.caltech.edu/~chima/publications/2007_PBCM_stishovite.pdf.  and references therein
  124. He, Duanwei; Zhao, Yusheng; Daemen, L.; Qian, J.; Shen, T. D.; Zerda, T. W. (2002). "Boron suboxide: As hard as cubic boron nitride". Applied Physics Letters 81 (4): 643. doi:10.1063/1.1494860. 
  125. 125.0 125.1 R Wirth; C. Vollmer; F. Brenker; S. Matsyuk; F. Kaminsky (2007). "Inclusions of nanocrystalline hydrous aluminium silicate "Phase Egg" in superdeep diamonds from Juina (Mato Grosso State, Brazil)". Earth and Planetary Science Letters 259 (3–4): 384. doi:10.1016/j.epsl.2007.04.041. 
  126. Liu, L.; Zhang, J.; Greenii, H.; Jin, Z.; Bozhilov, K. (2007). "Evidence of former stishovite in metamorphosed sediments, implying subduction to >350 km". Earth and Planetary Science Letters 263 (3–4): 180. doi:10.1016/j.epsl.2007.08.010. Archived on 2010-07-17. Error: If you specify |archivedate=, you must also specify |archiveurl=. https://web.archive.org/web/20100717031853/http://micron.ucr.edu/Public/KNB-papers/Liu-et-al-2007.pdf. 
  127. J. M. Léger, J. Haines, M. Schmidt, J. P. Petitet, A. S. Pereira & J. A. H. da Jornada (1996). "Discovery of hardest known oxide". Nature 383 (6599): 401. doi:10.1038/383401a0. 
  128. Smyth J. R.; Swope R. J.; Pawley A. R. (1995). "H in rutile-type compounds: II. Crystal chemistry of Al substitution in H-bearing stishovite". American Mineralogist 80 (5–6): 454–456. doi:10.2138/am-1995-5-605. http://rruff.geo.arizona.edu/doclib/am/vol80/AM80_454.pdf. 
  129. "Stishovite". San Francisco, California: Wikimedia Foundation, Inc. October 24, 2012. Retrieved 2012-10-23.
  130. "Tridymite". San Francisco, California: Wikimedia Foundation, Inc. August 25, 2012. Retrieved 2012-10-23.
  131. Pinkfud (3 September 2016). "tridymite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-20. {{cite web}}: |author= has generic name (help)
  132. 132.0 132.1 "Tridymite". Handbook of Mineralogy. III (Halides, Hydroxides, Oxides). Chantilly, VA, US: Mineralogical Society of America. ISBN 0-9622097-2-4. http://rruff.geo.arizona.edu/doclib/hom/tridymite.pdf. Retrieved December 5, 2011. 
  133. Kuniaki Kihara; Matsumoto T.; Imamura M. (1986). "Structural change of orthorhombic-I tridymite with temperature: A study based on second-order thermal-vibrational parameters". Zeitschrift für Kristallographie 177: 27–38. doi:10.1524/zkri.1986.177.1-2.27. 
  134. Heaney, P. J. (1994). "Structure and chemistry of the low-pressure silica polymorphs". Reviews in Mineralogy 29. 
  135. William Alexander Deer; R. A. Howie; W. S. Wise (2004). Rock-Forming Minerals: Framework Silicates: Slica Minerals, Feldspathoids and the Zeolites. Geological Society. pp. 22–. ISBN 978-1-86239-144-4. https://books.google.com/books?id=c4H5TsJbUdsC&pg=PA22. Retrieved 2 January 2012. 
  136. Pinkfud (2 November 2004). "feldspar". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2015-07-30. {{cite web}}: |author= has generic name (help)
  137. 137.0 137.1 137.2 137.3 137.4 IMA-NA (30 July 2015). "What is Feldspar?". North America: Industrial Minerals Association - North America (IMA-NA). Retrieved 2015-07-30.
  138. Chisholm, Hugh, ed (1911). Albite, In: Encyclopædia Britannica (11th ed.). Cambridge University, UK: Cambridge University Press. 
  139. 139.0 139.1 http://rruff.geo.arizona.edu/doclib/hom/albite.pdf Handbook of Mineralogy
  140. O.F. Tuttle, N.L. Bowen (1950): High-temperature albite and contiguous feldspars. J. Geol. 58(5), 572–583, https://www.jstor.org/stable/30068571
  141. "High Albite". www.mindat.org.
  142. Monalbite on Mindat
  143. J.P. Greenwood, P.C. Hess (1998): Congruent melting of albite: theory and experiment. J. Geophysical Research. 103(B12), 29815-29828
  144. "Cleavelandite". www.mindat.org.
  145. 145.0 145.1 145.2 145.3 "Associated minerals". www.mindat.org.
  146. [2] Albie Mineral Data
  147. [3] Anorthite}}
  148. "Significant Lunar Minerals" (PDF). In Situ Resource Utilization (ISRU). NASA. Retrieved 23 August 2018. {{cite web}}: |archive-date= requires |archive-url= (help)
  149. Handbook of Mineralogy
  150. Webmineral
  151. "Anorthoclase". www.minerals.net.
  152. AEJ Engel, CG Engel (1964). "Igneous rocks of the East Pacific rise". Science 146 (3643): 477. http://science.sciencemag.org/content/146/3643/477.short. Retrieved 2017-02-22. 
  153. Paul T. Robinson; Edwin H. Mckee; Richard J. Moiola (GSA Memoirs 1968). "Cenozoic volcanism and sedimentation, Silver Peak region, western Nevada and adjacent California". Geological Society of 116: 577-612. doi:10.1130/MEM116-p577. http://memoirs.gsapubs.org/content/116/577.abstract. Retrieved 2017-02-23. 
  154. "plagioclase". San Francisco, California: Wikimedia Foundation, Inc. October 16, 2012. Retrieved 2012-10-23.
  155. Pinkfud (6 November 2004). "feldspathoid". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2015-07-30. {{cite web}}: |author= has generic name (help)
  156. 156.0 156.1 David W. Phelps; David A. Gust; Joseph L. Wooden (November 1983). "Petrogenesis of the mafic feldspathoidal lavas of the Raton-Clayton volcanic field, New Mexico". Contributions to Mineralogy and Petrology 84 (2-3): 182-90. doi:10.1007/BF00371284. http://link.springer.com/article/10.1007/BF00371284. Retrieved 2016-02-12. 
  157. SemperBlotto (17 March 2006). "kaliophilite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-20. {{cite web}}: |author= has generic name (help)
  158. Jeff Weissman (1886). "Kaliophilite Mineral Data". Web Mineral. Retrieved 2017-02-22.
  159. Pinkfud (7 November 2004). "nepheline". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-20. {{cite web}}: |author= has generic name (help)
  160. Equinox (25 August 2011). "quadridavyne". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-20. {{cite web}}: |author= has generic name (help)
  161. Hudson Institute of Mineralogy (1997). "Quadridavyne". Hudson Institute of Mineralogy. Retrieved 2017-02-20.
  162. "Database of Zeolite Structures". iza-structure.org. International Zeolite Association. 2017. Retrieved 24 May 2021.
  163. Tschernich RW (1992). Zeolites of the World. Geoscience Press. ISBN 9780945005070. https://www.mindat.org/article.php/507/Mindat%27s+15th+Birthday+and+a+present+for+everyone. 
  164. "Database of Mineral Properties". International Mineralogical Association (IMA). Retrieved 9 February 2019.
  165. "Nickel-Strunz Classification - Primary Groups 10th ed". mindat.org. Retrieved 10 Feb 2019.
  166. First EL, Gounaris CE, Wei J, Floudas CA (2011). "Computational characterization of zeolite porous networks: An automated approach". Physical Chemistry Chemical Physics 13 (38): 17339–17358. doi:10.1039/C1CP21731C. PMID 21881655. 
  167. Rhanyeia (10 May 2008). "analcime". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-21. {{cite web}}: |author= has generic name (help)
  168. SemperBlotto (18 January 2007). "analcime". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-21. {{cite web}}: |author= has generic name (help)
  169. M Sacerdoti; A Sani; G Vezzalini (August 1999). "Structural refinement of two barrerites from Alaska". Microporous and Mesoporous Materials 30 (1): 103-9. doi:10.1016/S1387-1811(99)00028-1. http://www.sciencedirect.com/science/article/pii/S1387181199000281. Retrieved 2017-02-21. 
  170. 170.0 170.1 Michele Sacerdoti (May 2007). "The crystal structure of zeolite barrerite dehydrated in air at 400–450 C". Microporous and Mesoporous Materials 102 (1-3): 299-303. http://www.sciencedirect.com/science/article/pii/S1387181107000170. Retrieved 2017-02-21. 
  171. Equinox (25 August 2011). "barrerite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-21. {{cite web}}: |author= has generic name (help)
  172. Pinkfud (7 November 2004). "leucite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-20. {{cite web}}: |author= has generic name (help)
  173. SemperBlotto (27 April 2006). "natrolite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-21. {{cite web}}: |author= has generic name (help)
  174. Rhanyeia (5 April 2008). "natrolite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-21. {{cite web}}: |author= has generic name (help)
  175. Dana (1909). "Stellerite Mineral Data". Web Mineral. Retrieved 2017-02-21.
  176. SemperBlotto (1 November 2005). "stellerite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-21. {{cite web}}: |author= has generic name (help)
  177. Equinox (1 July 2010). "stilbite". San Francisco, California: Wikimedia Foundation, Inc. Retrieved 2017-02-21. {{cite web}}: |author= has generic name (help)
  178. M Slaughter (1970). "Stilbite-Na Mineral Data". American Mineralogist 55: 387-97. http://webmineral.com/data/Stilbite-Na.shtml#.WKyityhOTFI. Retrieved 2017-02-21. 
  179. G Cruciani; G Artioli; A Gualtieri; K Stahl; J C Hanson (1997). "Dehydration dynamics of stilbite using synchrotron X-ray powder diffraction, Sample: at T = 315 K". American Mineralogist 82: 729-739. http://webmineral.com/data/Stilbite-Ca.shtml#.WKyl0ChOTFI. Retrieved 2017-02-21. 

External links[edit | edit source]