PERTH (miningweekly.com) – Value enhancement programmes at diversified miner Independence Group’s Jaguar zinc/copper/silver/gold operation, in Western Australia, have demonstrated that the project’s mine life could be extended to 2022, while operational performance could also be improved.

A prefeasibility study completed on the Triumph deposit has confirmed that an estimated ore reserve of 1.2-million tonnes could extend the current Jaguar operation’s mine life to at least 2022. A process plant improvement study has demonstrated opportunities to achieve higher metallurgical recoveries for zinc and copper concentrates, and to grow a new revenue stream through production and sale of a new precious metals concentrate.

The mineral resource has been estimated at 2.2-million tonnes.

Independence MD Peter Bradford said that the second mining area would allow the processing plant to reach full capacity of 600 000 t/y, representing a 20% increase on historic throughputs.

“We can also realise favourable economics and technical viability by modifying the processing plant to improve copper and zinc recoveries, as well as growing a new revenue stream by producing a third concentrate of precious metals.”

Under an integrated development scenario, Bentley’s ore would be preferentially fed to the Jaguar mill and supplemented with the Triumph ore as necessary, to feed the 600 000 t/y of ore to the processing plant.

Jaguar’s processing plant is currently mine-constrained because the mining areas at Bentley are limited and can only produce at most 500 000 t/y.

The proposed development of Triumph would allow the processing plant to be run consistently at 600 000 t/y capacity, and ore production rates from the Triumph underground miner were expected to range from between 150 000 t/y to 600 000 t/y.

Meanwhile, Bradford told shareholders that Independence continued to reap the rewards of exploration investment at the Bentley mine, with the discovery of the Bentayga massive sulphide lense, as well as encouraging gold exploration results at Heather Bore.

“Independence will now advance these works programmes by pursuing and securing the necessary internal and external approvals to proceed with the Triumph mine development and Jaguar process plant improvements, as well as continue drilling Bentayga and other prospects that offer upside potential.”

A capital investment decision on the Triumph mine and the process plant improvements is expected in the first half of 2018.

Meanwhile, Independence on Wednesday reported a solid quarter for the three months ended June, with revenues increasing from A$83.9-million to A$114.2-million.

The increased revenue came on the back of increased zinc and copper concentrate shipments from the Jaguar mine, as well as a 5% increase in gold sold from the Tropicana gold operation, in Western Australia.

Zinc production from the Jaguar mine increased from 6 599 t to 7 399 t, while contained copper production increased from 688 t to 1 121 t, as Independence reported a 25% increase in ore mined and milled.

Gold production from the Tropicana joint venture mine with AngloGold Ashanti increased from 99 884 oz to 110 509 oz during the same period; however, Independence’s portion of gold sold from the operation was up 5% than the previous quarter to 32 396 oz.

Furthermore, nickel production at the Long mine declined slightly from 2 136 t to 2 069 t.

Meanwhile, operations at the Nova nickel project were ramping up towards the 1.5-million-tonne-a-year nameplate production capacity, which will be achieved in the September quarter of this year.

The Nova process plant milled 217 813 t during the quarter, with 17 703 t of nickel concentrate produced, at a grade of 14% and 3 617 t of copper concentrates at a grade of 29.5%.