The importance of mineralogical knowledge in the sustainability of artisanal gold mining: a mid-south Peru case
Mineralogy and gold processing techniques from several mining areas of the Nazca-Ocoña gold belt, Mid-South Peru, were investigated to assess the efficiency of gold extraction methods in relation to their mineralogy. The deposits from this belt are intrusion gold related to mineralization in quartz...
| Authors: | , , , , , , , |
|---|---|
| Format: | article |
| Publication Date: | 2019 |
| Country: | España |
| Institution: | Universitat Politècnica de Catalunya (UPC) |
| Repository: | UPCommons. Portal del coneixement obert de la UPC |
| Language: | English |
| OAI Identifier: | oai:upcommons.upc.edu:2117/166696 |
| Online Access: | https://hdl.handle.net/2117/166696 https://dx.doi.org/10.3390/min9060345 |
| Access Level: | Open access |
| Keyword: | Gold mines and mining -- Peru Amalgamation Sustainable development Artisanal mining Peru Gold Cyanidation Mines d'or -- Perú Amalgamació Desenvolupament sostenible Àrees temàtiques de la UPC::Enginyeria civil::Enginyeria de mines Àrees temàtiques de la UPC::Desenvolupament humà i sostenible::Cooperació per al desenvolupament::Projectes de cooperació |
| Summary: | Mineralogy and gold processing techniques from several mining areas of the Nazca-Ocoña gold belt, Mid-South Peru, were investigated to assess the efficiency of gold extraction methods in relation to their mineralogy. The deposits from this belt are intrusion gold related to mineralization in quartz veins. Native gold occurs as micrometric grains encapsulated in pyrite and in minor amounts in other sulfides and quartz. Electrum is found mainly in fractures of pyrite and attains up to 35 wt. % Ag. In addition to these occurrences, gold tellurides also occur and they are abundant in San Luis. Gold processing is carried out by amalgamation with mercury and/or cyanidation. The comparison of the gold grade in the mineralizations and in the residual tailings indicates that a significant amount of gold is not recovered using the mercury amalgamation process and also, in the case of the gold recovery by cyanidation, except when cement was added to the cyanide solution. This was due to an increase in the pH that favours the dissolution of the gold matrix. In the cyanidation process carried out in tailings previously treated with mercury, part of the mercury retained in them is released to the atmosphere or to the cyanidation fluids. |
|---|