The mineralogy of gold and its relevance to gold recoveries.

Processing of most gold ores, other than placers, involves conventional gravity separation and direct cyanidation. Refractory gold ores are not amenable to direct cyanidation and these ores require detailed mineralogical investigations to assist in determining the recovery processes. There are six mineralogical factors that can contribute to poorer recoveries: the nature of the gold-containing minerals; the grain size of the gold minerals; the nature of the gangue minerals; the associated sulphide minerals; coatings on gold; and chemically bound or "invisible gold".
Processing of most gold ores, other than placers, involves conventional gravity separation and direct cyanidation. Refractory gold ores are not amenable to direct cyanidation and these ores require detailed mineralogical investigations to assist in determining the recovery processes. There are six mineralogical factors that can contribute to poorer recoveries: the nature of the gold-containing minerals; the grain size of the gold minerals; the nature of the gangue minerals; the associated sulphide minerals; coatings on gold; and chemically bound or "invisible gold".