Apatite

A great resemblance of apatite to such minerals as beryl or olivine misled many mineralogists in the past, and it is still often mistaken for other minerals. Its name is derived from a Greek word απατείν (apatein), which means to deceive.^[1]

Apatite is actually a name of a whole group of minerals, not only one.^[1] Its chemical formula which includes fluorine, chlorine, and hydroxide indicates that those three elements can substitute for each other in different proportions.

Apatite crystals have many color varieties: green to yellow and purple to blue. Some crystals can also be transparent or multicolored.

Basic properties

Composition	(Ca,Ba,Pb,Sr)₅(PO₄,CO₃)₃(F,Cl,OH)
Class	Phosphates
Crystal system	Hexagonal
Mohs' hardness	5
Fracture	Conchoidal
Cleavage	None
Lustre	Glassy to resinous
Streak	White to grey
Localities	Portugal, Mexico, Switzerland, Russia, Brazil, Pakistan, Afghanistan, Germany, Canada

References

↑ ^1.0 ^1.1 Minerały i kamienie szlachetne by RBA Collecionables, S.A., ISBN 978-83-7813-150-2, 2012.

[RBA-1] 1.0 ^1.1 Minerały i kamienie szlachetne by RBA Collecionables, S.A., ISBN 978-83-7813-150-2, 2012.

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