![]() ![]() fingernail, so called for its resemblance with the translucence and color of a finger. Geological Survey (2005) Mineral Resources Data System: U.S. The name onyx is derived from the Greek word onux meaning claw or. ![]() Jay Ellis Ransom,1974, Gems and Minerals of America The most famous and exclusive of these precious stone marble is the Onyx which is predominantly found in the gas cavities of lava. Geological Survey, 2005, Mineral Resources Data System: U.S. ⓘ Grand Lake Mining District (Wolverine Mining District).Careless use of these names has resulted in the term 'Onyx' being incorrectly applied to a variety of banded materials that are not covered by the original definition of the name. Other names have been used over time for this material, such as " Mexican Onyx" and " onyx-marble". This is a carbonate material and not true onyx. In recent times the name has become confused with other banded materials, in particular banded calcite formed in cave systems such as the material found in Mexico and Pakistan and often carved, in fact the majority of carved material (such as book-ends, chess-sets, etc.) that are available today are made from this carbonate rock. The traditional method to make onyx is reported to have involved soaking the stone for months in honey or some sugar-rich solution, and then into concentrated sulphuric acid, which turned the sugar-infused bands black. In correct usage, the name refers to a (usually) black and white banded variety of agate, or sometimes a monochromatic agate with dark and light parallel bands (brown and white for example) - but traditionally the name was reserved for black and white banded agate, and brown varieties named Sardonyx. ![]()
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