如何寻找金矿（How to look for gold）.docVIP

如何寻找金矿（How to look for gold） I. geological survey of gold deposits The atomic number of gold is 79, and the element symbol Au is derived from Latin Aurnm, meaning aurora, A brilliant sun. Gold has only one stable isotope of 197, which is equiaxed at normal temperature Crystal, cubic face centered lattice. Natural crystalline forms are extremely rare and often irregularly granular, Agglomerate, flake, mesh, dendritic, fibrous and spongy aggregates. Pure gold is golden Color, containing impurities, a series of changes in color, silver or platinum when the color becomes pale, copper containing Yan Discoloration. High purity assay plate gold streak of red yellow, containing 10% silver streaks; As the bright golden yellow; silver containing 20 ~ 30% for the yellow grass has a silver content of more than 30%; Yellow with greenish hues; silver containing more than 50% silver. Gold is chemically stable and has a strong resistance to corrosion, from normal to high temperatures Non oxidation. Gold is not soluble in common acid and alkali, but soluble in aqua regia, alkali metal cyanide, Acid thiourea solution, bromine solution, boiling ferric chloride solution, aerobic potassium and sodium, Calcium, magnesium thiosulfate solution, etc.. Alkali metal sulfides corrode gold and produce soluble Auric sulfide. Humic acids in soil and metabolites of certain bacteria also dissolve trace amounts of gold. gold With sulphophile, often with sulphides such as pyrite, arsenopyrite, galena, stibnite and so closely co It is easy to form metals with sulfur, silver, palladium, platinum, copper, nickel, mercury, bismuth, antimony, rhodium and iridium Intermetallic compound. Gold has affinity for iron, iron in the gold rock than 3 orders of magnitude higher. Copper and silver are mostly enriched in sulfide phase, while gold and platinum are mostly concentrated in metal phase. Abundance of gold in the earths core For 2.6ppm, the mantle is 5ppb, and the crust is 1.8ppb. More than 99% of the gold