| Company | Gran Colombia Gold |
| Date | 2020 |
| Region | Caldas, Colombia |
| Commodities | Gold, Silver |
Executive Summary
This NI 43-101 Technical Report details the recovery methods for the Marmato Project operated by Gran Colombia Gold. The current operations utilize a 1,200 tpd process plant to recover gold and silver from the Upper Zone, employing a flowsheet that includes crushing, grinding, gravity concentration, flotation, cyanidation, and Merrill-Crowe precipitation. Historical performance from 2013 to 2019 shows gold recovery averaging 86.5% and silver recovery averaging 33.2%, with operating costs averaging US$13.08/t processed.
The report also evaluates the development of the MDZ, a deeper zone below current operations, which requires a new 4,000 tpd plant. The selected flowsheet for MDZ involves gravity concentration followed by cyanidation of the gravity tailing, utilizing SAG and ball mill grinding, agitated cyanide leaching, and Carbon-in-Pulp (CIP) adsorption. This proposed expansion targets higher gold recovery of 95% and silver recovery of 40%, with estimated operating costs of US$13.34/t and a capital cost of US$65.6 million.
Key operational parameters for the current plant include the use of jaw and cone crushers, ball mills, jigs, and flotation cells. The MDZ plant design incorporates centrifugal gravity concentrators and electrowinning for final product recovery. Both circuits utilize cyanide destruction processes to manage tailings and comply with environmental standards.
Website: https://www.iisd.org/itn/2022/03/30/the-conflict-between-traditional-miners-in-marmato-and-canadian-transnational-mining-companies-another-isds-dispute-over-natural-resources-in-colombia/
Report Date: 2020
Region: Caldas, Colombia
Project Status:
Commodity: Gold, Silver
Throughput:
Mine Life:
Mine Type:
Ore type:
Technical report and processing history
The following archived source profiles have been consolidated here to preserve the project’s processing history and study context.
Marmato Project — 2019 Technical Report
Marmato Project — 2019 Technical Report
| Company | Gran Colombia Gold |
| Date | 2019 |
| Region | Colombia |
| Commodities | Gold, Silver |
Executive Summary
This NI 43-101 Technical Report details the recovery methods and operational performance for the Marmato Project operated by Gran Colombia Gold (GCM). The current operations utilize a 1,200 tpd process plant to recover gold and silver from underground mining operations in the Upper Zone. The plant employs a flowsheet incorporating three-stage crushing, closed-circuit ball mill grinding, gravity concentration, flotation, cyanidation, and Merrill-Crowe zinc precipitation to produce a final dore product. Operating performance from 2013 to 2019 shows gold recovery averaging 86.5% and silver recovery averaging 33.2%, with operating costs averaging US$13.08/t processed.
The report also evaluates the development of the Marmato Deep Zone (MDZ), which lies below current mining operations. A new 4,000 tpd plant is proposed to process MDZ material exclusively. After evaluating three flowsheet options, the selected design includes gravity concentration followed by cyanidation of the gravity tailing and Carbon-in-Pulp (CIP) adsorption. This proposed plant targets 95% gold recovery and 40% silver recovery, with estimated operating costs of US$13.34/t and a conceptual capital cost of US$65.6 million.
Reports
Website: https://www.iisd.org/itn/2022/03/30/the-conflict-between-traditional-miners-in-marmato-and-canadian-transnational-mining-companies-another-isds-dispute-over-natural-resources-in-colombia/
Report Date: 2019
Region: Colombia
Project Status:
Commodity: Gold, Silver
Throughput:
Mine Life:
Mine Type:
Ore type:
