Illustrated Companion to the Latin Dictionary/Alexandrinum opus

This article incorporates text from a publication now in the public domain: Rich, Anthony (1849). The illustrated companion to the Latin dictionary, and Greek lexicon. p. vi. OCLC 894670115. https://archive.org/details/illustratedcompa00rich. 

ALEXANDRI'NUM OPUS. A particular kind of mosaic work, especially used for the flooring of rooms, and belonging to the class of pavements termed sectilia, the distinctive character of which consisted in this, that the frets or patterns forming the designs, were composed by the conjunction of only two colours, red and black for instance, on a white ground, as in the example (Alexandrinum_opus/1.1), which represents a portion of a pavement in a house at Pompeii. (Lamprid. Alex. Sev. 25.) The words of Lampridius seem to imply that this description of mosaic was first introduced by Severus; but such a notion is rendered untenable by the numerous specimens of it in the Pompeian houses. We must, therefore, understand that Severus merely introduced the custom of forming such pavements by the contrast of two sorts of marble different in colour and quality from those which had been previously employed for the purpose, viz. porphyry and Lacedaemonian marble.

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  Alexandrinum opus/1.1