Processing, smelting and refining gold | World Gold Council
Jul 07, 2020· For extracting gold from lowgrade ores, heap leaching is practiced; huge heaps are sprayed with a dilute solution of sodium cyanide, and this percolates down through the piled ore, dissolving the gold. There are very well defined rules for the safe and responsible use of cyanide – as laid out in the International Cyanide Code. Gold refining