Advances in geochemical research on gold in coal

WANG Wen-feng; QIN Yong; SANG Shu-xun; WANG Jun-yi; WANG Ran

Abstract：Current studies on gold in coal in world were introduced, and the distribution, occurrence and accumulation causes of gold in coal were discussed in detail. Gold has a lower abundance in most coals throughout the world. Howev-er, anomalous gold content was found in some coals, particularly in the coal seams framed by gold mines or Au-special-ized rocks and these seams were regarded as the most promising for gold accumulation. Gold has an obviously higher content in coals from Southwestern Guizhou Province containing many gold deposits than in coals from the North, pos-sessing an ore-forming potential. Sulfide (mainly pyrite), quartz and carbonate veins affected by low-temperature hydrotherm should be the main carriers of gold in coal. Additionally, gold is absorbed by humic acid and clay miner-als, which are also important modes of occurrence of gold in coal. For any gold deposit, there exist many geological fac-tors resulting in the gold accumulation, of which the organic matter, the low-temperature hydrothermal process, the mi-gration of nano-gold in gas phases and the surface behaviour of minerals are likely to be the most effective factors for gold accumulation in coal.