Pyrites Plant

Ownership: 100% Fresnillo plc
Location: Zacatecas, Fresnillo District
Facilities: Leaching plant at the Saucito mine, flotation plant at the Fresnillo mine
Commercial Production: 2Q18 (phase I), 2H20 (phase II)
Anticipated Production: Annual average 3.5 moz silver and 13.0 koz gold
Capex: US$ 155 million

The Pyrites plant is expected to improve overall recoveries of gold and silver, and therefore maximise production in the Fresnillo district; expected to total an average of 3.5 moz silver and 13 koz gold per year once both phases are operating at full capacity. 

The second phase, a flotation circuit, will treat the ongoing and historical tailings from the Fresnillo mine to produce a pyrites concentrate which will be sent to a filtration plant and then on to the leaching plant at Saucito, the final part of the process to produce the precipitates. Commissioning of phase II of the Pyrites plant set for 2H 2020.

Pyrites Plant (Phase I)

 

1Q19

1Q18

% change

4Q18

Ore processed (t)

47,846

N/A

N/A

56,699

         

Production

       

Silver (koz)

306

N/A

N/A

470

Gold (oz)

1,100

N/A

N/A

1,952

         

Ore grades

       

Gold (g/t)

268

N/A

N/A

348

Silver (g/t)

2.1

N/A

N/A

2.5

Overview and Key developments:

  • The project will improve overall recoveries of gold and silver by processing historical and ongoing tailings from Fresnillo and Saucito mines.

  • The plant will froth float pyrite concentrates that will be leached in a 2,000 tpd dynamic leaching plant and Merrill Crowe plant to produce precipitates.

  • First stage completed: commissioned leaching plant at Saucito on time (2Q18), following a US$54.6 million investment.

  • Second stage: Construction of the flotation plant at Fresnillo expected 2H20, delayed due to a longer than anticipated permitting process.

Highlights - 1Q19

  • The leaching plant of the Pyrites plant at Saucito contributed 306 koz of silver and 1,100 oz of gold in 1Q19, down 34.9% and 43.6% respectively vs. 4Q18. This resulted from the expected lower ore grade material processed at the plant as the stock pile with higher silver and gold content is depleted.

  • Expected silver ore grade for 2019 continues to be between 190-210 g/t.