Epithermal deposits have, and continue to significantly contribute to gold and silver production world-wide. In addition to gold and silver which are the major economic minerals found in these deposits, varying amounts of mercury, copper, lead, zinc and tin, may be present in these systems. Ore bodies can be made up of mineralized veins, stockworks, breccias and/or the mineralization can be disseminated. The classifications of high-, intermediate- and low-sulfidation (Einaudi, et al, 2003) have been used in the last couple of decades to describe the stability of sulfide minerals.
We will see a variety of these characteristics on this field trip, such as other minerals produced from the high-sulfidation systems at the Paradise Peak district and the Goldfield district were mercury, and copper and lead respectively. The Paradise Peak (high-sulfidation system) and Round Mountain (low-sulfidation system) districts have produced, and/or are producing gold-silver from disseminated ore bodies in tuffs. At the Goldfield district we will see the quartz-alunite veins typical of high-sulfidation systems, and at Monte Cristo (Gilbert district) we will see characteristics related to intermediate sulfidation systems.
The opportunity to observe a variety of characteristics associated with high-, intermediate- and low-sulfidation systems will hopefully give the participants some additional tools for exploring for more of these deposits in Nevada.