Onyx marbles of local source are polished at Phoenix.
The gems of onyx, carnelian and agate are later and bear various figures, and in some cases Arabic inscriptions.
The latter, however, though thriving as an aviary bird, has failed at large in England, as did the bob-white (Onyx virginianus) both there and in New Zealand.
Some marble is quarried at Beaver in Beaver county, and Utah onyx has been used for interior decoration, notably in the city and county building of Salt Lake City.
For particulars respecting the special characters, modes of occurrence and localities of the more important varieties of quartz, reference may be made to the following articles: AGATE, AMETHYST, AVENTURINE, BLOODSTONE, CAIRNGORM, CARNELIAN, CAT'S-EYE, CHALCEDONY, CHRYSOPRASE, FLINT,HELIOTROPE,JASPER, MOCHASTONE, ONYX, ROCK-CRYSTAL, SARD, SARDONYX.