| Company | Cusi Operations |
| Date | 2019-2020 |
| Region | Cuauhtémoc City, Mexico |
| Commodities | Metal |
Executive Summary
The Cusi concentrator is located in the outskirts of Cuauhtémoc City, approximately 50 km by road from the Cusi operations. The facility processes mineralized material delivered by dump trucks, each hauling approximately 20 tonnes of material. In 2019, the concentrator received 285,236 tonnes of mineralized material. Production volumes in 2020 were lower, with 117,320 tonnes delivered in the first eight months of the year.
Production in 2020 was significantly disrupted by the Covid-19 pandemic. Specifically, no run of mine mineralized material was processed during the months of April, May, or June 2020. This disruption impacted the overall throughput and recovery metrics for the reporting period compared to the previous year.
Recent improvements implemented at the plant have resulted in higher metal recoveries despite the operational challenges. The concentrator continues to serve as the primary processing facility for the Cusi operations, handling the delivered mineralized material to extract valuable metals.
Processing Profile
- Crushing: Not specified in text
- Milling: Not specified in text
- Flotation: Concentrator
- Leaching: Not specified in text
Website: https://cusi.com/
Report Date: 2019-2020
Region: Cuauhtémoc City, Mexico
Project Status:
Commodity: Metal
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.
Cusi — 2020 Technical Report (PEA)
Cusi — 2020 Technical Report (PEA)
| Company | Sierra Metals Inc. |
| Date | 2020 |
| Region | Cuauhtemoc, Mexico |
| Commodities | Lead, Zinc, Silver, Gold |
Executive Summary
The Cusi concentrator, operated by Sierra Metals Inc., processes mineralized material delivered by dump trucks to the Mal Paso and El Triunfo mills. In 2019, the facility processed 285,236 tonnes of material, producing primarily lead concentrate with minor zinc concentrate. The operation faced disruptions in 2020 due to the Covid-19 pandemic, with no run of mine material processed in April, May, or June.
Metallurgical performance data from 2019 to August 2020 indicates lead recovery reached 74% and silver recovery averaged 77.3%. Gold recovery showed higher variability, averaging 36.8%. The lead concentrate produced has high silver content, making it attractive to smelters despite lead grade being below typical market values. The plant utilizes a conventional crushing and grinding circuit followed by flotation.
Processing Profile
Reports
- reports/2020_SierraMetals_Cusi_PEA
Website: https://www.mexicominingcenter.com/sierra-metals-completes-the-sale-of-the-cusi-mine/
Report Date: 2020
Region: Cuauhtemoc, Mexico
Project Status:
Commodity: Lead, Zinc, Silver, Gold
Throughput:
Mine Life:
Mine Type:
Ore type:
Cusi Mine — 2018 Amended NI 43-101 Technical Report
Cusi Mine — 2018 Amended NI 43-101 Technical Report
| Company | Dia Bras |
| Mine | Cusi Mine |
| Date | 2018 |
| Region | Mexico |
| Commodities | Lead, Zinc, Silver, Gold |
| Mine Type | Not Specified |
| Throughput | 186,898 t (2016) |
| Mine Life | Not Specified |
| Status | Operating |
Executive Summary
The Cusi concentrator, located in the outskirts of Cuauhtemoc City, Mexico, processes ore from Cusi operations via two interconnected plants: the Malpaso mill and the El Triunfo mill. Both facilities share a single crushing circuit that reduces Run-of-Mine (ROM) feed to minus ¼ inch before feeding the respective ball mills. The processing circuit is designed for conventional ball mill and flotation operations capable of producing both lead and zinc concentrates, with lead concentrate historically representing the higher percentage of production. In 2016, the facility processed 186,898 tonnes of ore, yielding 5,442 tonnes of lead concentrate and 1,540 tonnes of zinc concentrate.
Metallurgical performance data from 2014 to 2016 indicates varying recovery rates for silver, lead, and zinc. The 2016 head grades averaged 175.88 gr/t Ag, 0.78% Pb, 0.71% Zn, and 0.22 gr/t Au. Lead recovery in concentrate averaged around 70-79% during this period, while zinc recovery was commissioned later, showing 38% recovery in 2016. Additionally, the El Triunfo plant includes a cyanide leach facility used for legacy tailings, though this circuit has been idled since mid-2012 with no scheduled restart.
Production Data
| Year | Tonnage (t) | Pb Conc (t) | Zn Conc (t) | Ag (oz) | Pb (t) | Zn (t) | Au (oz) |
|---|---|---|---|---|---|---|---|
| 2014 | 155,268 | 962 | na | 630,160 | 962 | na | 1,289 |
| 2015 | 202,033 | 1,246 | na | 873,496 | 1,246 | na | 831 |
| 2016 | 186,898 | 5,442 | 1,540 | 739,707 | 1,864 | 818 | 954 |
Source: Dia Bras, 2017
Website: https://www.silvercomining.com/projects/cusi-mine-complex/project-history/
Report Date: 2018
Region: Mexico
Project Status: Operating
Commodity: Lead, Zinc, Silver, Gold
Throughput: 186,898 t (2016)
Mine Life: Not Specified
Mine Type: Not Specified
Ore type:
Cusi Mine — 2018 Technical Report (PEA)
Cusi Mine — 2018 Technical Report (PEA)
| Company | Sierra Metals |
| Date | 2018 |
| Region | Cuauhtemoc, Mexico |
| Commodities | Lead, Silver, Zinc, Gold |
| Mine Type | Not Specified |
| Throughput | 650 tpd (Current), 1200 tpd (Planned) |
| Mine Life | Not Specified |
| Annual Production | 1,864 t Pb, 818 t Zn, 739,707 oz Ag, 954 oz Au (2016) |
| Status | Operating |
Executive Summary
This report details the recovery methods and processing capacity for the Cusi Mine, operated by Sierra Metals. The existing Mal Paso plant currently processes 650 tpd, with plans to expand capacity to 1200 tpd by Q1 2019 through equipment upgrades including additional ball mills and flotation cells. A separate modular plant is proposed at Cusihuariachi to handle an additional 1500 tpd, bringing the combined processing capacity to 2700 tpd by mid-2021.
The processing circuit is designed for sulphide ores, utilizing conventional crushing, grinding, and flotation methods to produce separate commercial grade Pb/Ag and Zn concentrates. Metallurgical recoveries for 2016 showed 82% Pb recovery and 38% Zn recovery. The proposed Cusihuariachi plant aims to reduce transportation and processing costs by USD $5/t compared to the current Mal Paso configuration.
Processing Profile
Reports
Website: https://www.mexicominingcenter.com/sierra-metals-completes-the-sale-of-the-cusi-mine/
Report Date: 2018
Region: Cuauhtemoc, Mexico
Project Status: Operating
Commodity: Lead, Silver, Zinc, Gold
Throughput: 650 tpd (Current), 1200 tpd (Planned)
Mine Life: Not Specified
Mine Type: Not Specified
Ore type:
