The 2023 technical report on Guanajuato Silver's Topia property in Durango describes a small conventional flotation plant, upgraded in 2019 and 2020 and switched to dry-stack tailings in 2017, that milled 96,127 tonnes between August 2022 and December 2023.
The Technical Report on the Topia Property, Durango, Mexico, prepared for Guanajuato Silver Company Ltd. by APEX Geoscience Ltd. and P&E Mining Consultants Inc. with an effective date of December 31, 2023, covers the Topia silver-lead-zinc operation in the historical Topia Mining District, about 235 km northwest of the city of Durango. Ore from the Topia mines, and material bought from local miners, is processed at the Topia plant just north of the Topia townsite, near the Argentina mine entrance. The plant uses conventional crushing, grinding and flotation to make lead and zinc sulphide concentrates.
Critical Data
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Report effective date | December 31, 2023 | Not applicable | Prepared for Guanajuato Silver Company Ltd. |
| Nominal plant capacity | About 260 | t/d | Flotation concentrator |
| Tonnes milled, Aug 2022 to Dec 2023 | 96,127 | t | Includes 11,342 t bought from local miners |
| Head grade, period total | 342.71 g/t Ag, 0.95 g/t Au, 2.60% Pb, 3.30% Zn | Not applicable | Table 17.1 |
| Silver recovery | 92.27 | % | Period total |
| Gold recovery | 62.12 | % | Period total |
| Lead recovery | 89.21 | % | Period total |
| Zinc recovery | 83.51 | % | Period total |
| Metal produced, period total | 979,060 oz Ag, 1,822 oz Au, 4,904,566 lb Pb, 5,733,017 lb Zn | Not applicable | Topia ore plus purchased material |
| Final grind | 65% passing 74 | µm | Ball mill and cyclone circuit |
| Concentrate moisture | 10 | % | After disc filters |
| Electricity use | About 363,000 | kWh/month | National grid supply |
| Tailings | Dry stack | Not applicable | Filtration facility operating since 2017 |
Overview
The Topia plant works in four stages: crushing, milling, flotation and drying. Coarse ore is placed in one of six bins, which let the operators sort material for batch processing and blending. Material delivered by local miners is processed separately so that its grades and recoveries can be monitored accurately.
Between August 2022 and December 2023, 84,785 tonnes from the Topia mines and 11,342 tonnes from other local miners were milled, 96,127 tonnes in all. Topia's own production made up about 91% of the material processed in 2022 and 87% in 2023. Over the period the plant recovered 92.27% of the silver, 62.12% of the gold, 89.21% of the lead and 83.51% of the zinc, producing 979,060 ounces of silver, 1,822 ounces of gold, 4,904,566 pounds of lead and 5,733,017 pounds of zinc. Zinc recovery fell from 87.48% in August to December 2022 to 81.69% in 2023, while silver recovery held at about 92.3% in both periods.
Key Process Stages
Crushing. From the bins, ore passes through a grizzly to a 15 by 24 inch jaw crusher and then over a 6 by 12 ft vibrating screen. Oversize above ¾ inch goes to a secondary cone crusher, and crushed material reports to a 200 t ore bin.
Grinding. The grinding circuit has three ball mills and two 10 inch cyclones. Fine ore goes either to a 6 by 14 ft or a 5 by 10 ft ball mill. With the 5 by 10 ft mill, product passes through the cyclones and oversize returns to that mill. With the 6 by 14 ft mill, cyclone oversize goes to a 4 by 8 ft ball mill operating in closed circuit with the cyclones. The final grind is 65% passing 74 µm.
Flotation. The ground slurry passes to a lead flotation circuit of primary and secondary rougher and cleaner cells, followed by a zinc circuit of the same configuration.
Concentrate handling. Disc filters dry the lead and zinc concentrates to 10% moisture. Trucks carry them to the port of Manzanillo for sale to a concentrate buyer.
Tailings. The wet tailings system was replaced by dry stacking when a filtration facility started in 2017. The site has a tailings thickener and filter press plant, and tailings are stored at the Victoria Phase II tailings storage facility.
Additional Interesting Data and Summary
Further upgrades to the crushing plant, flotation circuits and ball mills in 2019 and 2020 improved the plant's overall operating efficiency. Power comes from the Mexican national grid: the plant uses about 363,000 kWh a month against an electrical capacity of 1,030,000 kWh. Water comes from unused shafts and underground sources, with recirculated water from the tailings facilities, and the report states the supply was sufficient at the effective date. An on-site laboratory handles about 75 to 80 samples a day for gold, silver, lead, zinc, copper and iron. Access is by 350 km of paved and gravel road from Durango, about eight hours' travel, and the road takes 30 tonne articulated concentrate trucks.
In summary, Topia is a small, long-established silver-base metal flotation plant that blends its own ore with purchased material, recovers just over 92% of the silver into lead and zinc concentrates, and has moved its tailings to dry stacking.
Key Processes
- Bin storage for sorting and blending
- Jaw and cone crushing
- Ball milling with cyclone classification to 65% passing 74 µm
- Sequential lead and zinc flotation, roughers and cleaners
- Disc filtration of concentrates to 10% moisture
- Tailings thickening, filter pressing and dry stacking
Source: Technical Report on the Topia Property, Durango, Mexico, prepared for Guanajuato Silver Company Ltd., effective date December 31, 2023.
Technical report and processing history
The following archived source profiles have been consolidated here to preserve the project’s processing history and study context.
NI 43-101 Report on the Topia Mine
NI 43-101 Report on the Topia Mine
| Company | Great Panther Silver Limited |
| Mine | Topia Mine |
| Date | May 2014 |
| Region | Durango, Mexico |
| Commodities | Gold, Silver, Lead, Zinc |
Executive Summary
This section of the NI 43-101 Technical Report details the recovery methods employed at the Topia Mine metallurgical plant. The process flow begins with coarse ore segregation into six bins, followed by primary crushing using a 15” x 24” jaw crusher and screening via a 6’ x 12’ vibratory screen. Oversize material is secondary crushed before entering a fine ore bin.
Grinding is achieved through a circuit comprising three ball mills and two 10”-dia. cyclones, targeting a final grind size of 65% passing 74µm. The ore stream then proceeds to a lead flotation circuit with primary and secondary rougher and cleaner cells, followed by a similarly configured zinc circuit. Concentrates are filtered to 10% moisture using disc filters and shipped to the port of Manzanillo.
At the time of the report, upgrades were underway to increase flotation capacity and improve water reclamation via a decant tower. The mill performance confirms that gold, silver, lead, and zinc can be recovered using these conventional processes.
Website: https://en.wikipedia.org/wiki/Great_Panther_Mining
Report Date: May 2014
Region: Durango, Mexico
Commodity: Gold, Silver, Lead, Zinc
Technical Report on the Topia Property, Durango, Mexico
Technical Report on the Topia Property, Durango, Mexico
| Company | Topia Project |
| Date | 2023 |
| Region | Durango, Mexico |
| Commodities | Silver, Gold, Lead, Zinc |
| Mine Type | Underground |
| Throughput | 96,127 tonnes (Aug 2022 – Dec 2023) |
| Annual Production | 979,060 oz Ag, 1,822 oz Au, 4,904,566 lbs Pb, 5,733,017 lbs Zn |
| Status | Operating |
Executive Summary
The Topia Property Technical Report details the processing operations at the Topia processing plant located in Durango, Mexico. The facility processes mineralized material from the Topia mine and purchased material from local miners using conventional crushing, grinding, and flotation methods to produce lead and zinc sulphide concentrates. The plant transitioned to a dry stack tailings system in 2017 and underwent efficiency upgrades in 2019 and 2020.
Production data from August 2022 to December 2023 indicates a total throughput of 96,127 tonnes milled. This period yielded 979,060 ounces of silver, 1,822 ounces of gold, 4,904,566 pounds of lead, and 5,733,017 pounds of zinc. The plant operates with high recovery rates, particularly for silver at 92.27% and lead at 89.21%, while gold recovery sits at 62.12%.
The processing circuit includes primary and secondary crushing, followed by a grinding circuit utilizing multiple ball mills and cyclones. Flotation circuits are configured separately for lead and zinc, utilizing rougher and cleaner cells. Concentrates are dried to 10% moisture using disc filters and shipped to the port of Manzanillo. The plant relies on the Mexican National electrical grid and local underground water sources.
Operational Details
Processing Profile
- Crushing: Primary Jaw Crusher (15×24 inch), Secondary Cone Crusher
- Milling: Ball Mills (6×14 ft, 5×10 ft, 4×8 ft)
- Flotation: Lead and Zinc circuits (Primary/Secondary Rougher and Cleaner)
- Tailings: Dry Stack (Filtration facility)
Reports
Website: https://www.gsilver.com/mines/topia-mine
Report Date: 2023
Region: Durango, Mexico
Project Status: Operating
Commodity: Silver, Gold, Lead, Zinc
Throughput: 96,127 tonnes (Aug 2022 – Dec 2023)
Mine Life:
Mine Type: Underground
Ore type:
Topia — 2022 Technical Report
Topia — 2022 Technical Report
| Company | Topia Project |
| Date | 2022-02-11 |
| Region | Durango, Mexico |
| Commodities | Gold, Silver, Lead, Zinc |
Executive Summary
This NI 43-101 Technical Report outlines the recovery methods employed at the Topia metallurgical plant. The process flow begins with coarse ore segregation into bins, followed by crushing through a 15” x 24” jaw crusher and a secondary cone crusher. The ore is then screened and ground using a circuit comprising three ball mills and cyclones to achieve a final grind size of 65% passing 74μ.
The plant utilizes conventional flotation circuits for lead and zinc recovery, with concentrates dried to 10% moisture content using disc filters. Tailings management has evolved from impoundment behind a dam to dry stacking, with a new dry stack site receiving final permitting in 2020. The mill demonstrates that gold, silver, lead, and zinc can be recovered using these conventional processes.
Utilities for the plant include electricity from the Mexican national grid and water stored in underground shafts and dammed levels. Processing materials are transported by road access from Durango. Upgrades to the crushing plant, flotation circuits, and ball mills were completed in 2019 and 2020 to improve operational efficiencies.
Website: https://dropstab.com/uk/coins/hytopia/exchanges
Report Date: 2022-02-11
Region: Durango, Mexico
Project Status:
Commodity: Gold, Silver, Lead, Zinc
Throughput:
Mine Life:
Mine Type:
Ore type:
