onyx

onyx (ŏn`ĭks), variety of cryptocrystalline quartz, differing from agate only in that the bands of which it is composed are parallel and regular. Its appearance is most striking when the bands are of sharply contrasting colors; black and white specimens are often used for cameos. Onyx was used in Roman times for the fabrications of vases and cups. Sardonyx contains onyx and carnelian or sard. "Onyx marble," "Mexican onyx," and "Oriental alabaster" are terms applied to travertine.

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onyx

Striped, semiprecious variety of the silica mineral agate with white and black alternating bands. Other varieties include carnelian onyx, with white and red bands, and sardonyx, with white and brown bands. Its properties are the same as those of quartz. Onyx is used in carved cameos and intaglios because its layers can be cut to show a colour contrast between the design and the background. It is found worldwide, but chiefly in India and South America.

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Onyx

A family of graphics supercomputers from SGI that use the MIPS R10000 CPU and range from single-processor workstations to rack-mounted systems with 128 CPUs. They use SGI's InfiniteReality graphics subsystem which processes geometry, imaging and video data in real time.

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onyx

1. a variety of chalcedony with alternating black and white parallel bands, used as a gemstone. Formula: SiO₂ - PLEASE CHECK FORMULA

2. a compact variety of calcite used as an ornamental stone; onyx marble. Formula: CaCO₃

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onyx

provokes disagreement and separates lovers. [Gem. Symbolism: Kunz, 98–99]

See : Discord