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The Epic Interactive Encyclopedia 1998
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Epic Interactive Encyclopedia, The - 1998 Edition (1998)(Epic Marketing).iso
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Onyx
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INFOTEXT
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1992-09-01
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A semiprecious variety of chalcedonic silica
(Si02) in which the crystals are too fine to
be detected under a microscope, a state known
as cryptocrystalline. It has straight
parallel bands of different colours: milk-
white, black, and red. Sardonyx, an onyx
variety, has layers of brown or red carnelian
alternating with lighter layers of onyx. It
can be carved into cameos.