Explanation

The coordination type belongs to elemental minerals. The chemical formula is Au. Pure gold is rare and often contains isomorphic substitutes of silver, as well as Cu, Fe, Pd, Bi, Pt, Ni, and Te, Se, Ir, etc. Those with a silver content of 15% -50% are called silver gold mines (Au, Ag). Equiaxed crystal system, copper type structure. Intact crystal form is rare. Generally, it appears as an irregular granular, clumpy, thin sheeted, branched, or sponge like aggregate. It also often occurs as small inclusions in pyrite, chalcopyrite, galena or quartze. The color and stripes are both golden yellow, becoming lighter yellow as the silver content increases. Metallic luster, without cleavage. Mohs hardness 2-3, density 15.6-18.3g/cm3. It has ductility, stable chemical properties, and is only soluble in aqua regia. A good conductor of electricity and heat. It occurs in gold bearing quartz vein of hydrothermal origin. It is associated with pyrite, magnetite, arsenojpyrite, sphalerite, galena, etc. in high-temperature hydrothermal gold deposits, pyrite, galena, sphalerite, chalcopyrite, etc. in medium temperature hydrothermal gold deposits, and pyrite, galena, sphalerite, argent, chalcopyrite, etc. in low-temperature hydrothermal gold deposits. China has a wide distribution of placer gold, which is famous for Jinsha River, Heilongjiang and Yuanshui River basins in Hunan.

Classification