“Look for gold where gold is said to be” (Don McKinnon- discoverer of Hemlo).
Gold deposits encompass a wide variety of geological environments. Depending on the deposit type (i.e. epithermal, mesothermal, porphyry-style, disseminated, BIF-hosted, IOCG, skarns, lode, etc.), they are associated with a wide-range of alteration assemblages. Secondary minerals, although specific to deposit type, greatly vary and include quartz or chalcedony, tourmaline, clay minerals, albite, adularia, orthoclase or microcline, carbonate (often ankerite), calc-silicates, specular hematite, sericite, chlorite, fuchsite, alunite, and many more….
The photomicrographs below show a few type of gold deposits, prospects and associated alteration types.
In the Petrographic Reports special emphasis will be placed on identifying secondary minerals associated with gold, as it is one of the most important criteria in distinguishing between various gold deposit types. Visit About GeoConsult to see a list of gold deposits GeoConsult had been involved with (in the capacity of a mineralogist and/or a geochemist).
For detailed information on Petrographic Reports, visit GeoConsult Services.
(x-axis of gold photos: 0.64mm, others: 1.6mm)