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| Formula: | Au |  Click to see a larger image |
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| Crystal: | Isometric | |||
| Hardness: | 2.5-3 | |||
| Spec. Gr.: | 19.3 | |||
| Streak: | Golden yellow (pure) | |||
| Cleavage: | None | |||
| Location: | Forest Hill Mine, Placer County, California |
| Gold occurs in octahedral and variously elongated crystals. It is the most easily malleable metal and effortlessly conducts electricity. Typically it is gold yellow but changes with the admixture of silver, nickel, or copper. Gold is the standard metal stored in the state reserves, and finds major uses in jewelry, in the electrical industry, and in dentistry. Gold crystals tend not to tarnish and therefore are very brilliant. Gold crystals are found in Romania, Venezuela, Russia, and various deposits in Australia. Currently, many fine crystals are being mined in a little known mine in Placer County, California. Gold was the first metal known and used by ancient man. When streams flowed clearly over sandy bottoms, alluvial gold was easily seen. The oldest known objects fashioned of gold were discovered in 1972 at Grupina, near Varna, Bulgaria, and date from about 4000 BC. Egyptians, in very early pharaonic times, mined gold at Barramija near Berenice and the Sudanese border on the Red Sea. They also made the Turin Papyrus, possibly the world's oldest map of a gold mine. |
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Bibliography: Svenek, Jaroslav, Minerals, 1987, pg. 34-35. Bancroft, Peter, Gem and Crystal Treasures, 1984, pg 89-91. |
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