TORONTO (miningweekly.com) – Colorado-based Atna Resources’ TSX-listed shares slid by more than 41% after it slowed the pace of underground mining operations at its flagship Pinson gold mine, in Nevada, as a result of the current gold market.

Atna said operations at the mine were being temporarily downsized to focus on mining developed reserves, while maintaining core personnel and contractors.

“The immediate goal of this decision is to produce sufficient gold sales to support operations and maintain underground infrastructure, while the mine plan is being re-engineered to reduce overall cost structures,” the miner said.

It added that all aspects of the current mining methods employed at Pinson, combined with existing third-party mining, transportation and processing contracts, would be reviewed during this evaluation. As a result, the Pinson mine’s production guidance was also withdrawn.

In March, Atna had entered into an agreement with Veris Gold to process Pinson's ore in lots of 5 000 t or greater, providing an outlet for mixed oxide and sulphide ore, which allowed Atna to decrease its expected working capital.

The shipment of Pinson ore to Veris’ Jerritt Canyon roaster started in April.

In February, Pinson had also been granted a permit modification to allow for production to be expanded to 400 000 t/y.

Atna said it was able to proceed with its mining re-engineering programme because of the significant underground development it had completed at Pinson, which had provided five operating ore stopes for production activities.

The company said it had also started a feasibility study to determine the potential for openpit mining as a means to increase overall project return.

"Pinson possesses a robust gold resource that may be mined by both underground and openpit methods. Our focus is to improve the overall cost structures and to optimise the cash flows from the project,” president and CEO James Hesketh said.

Atna also operates the Briggs gold mine and a number of other development projects.

In the quarter ended March 31, the gold miner reported a net profit of $800 000, and gold sales of 8 420 oz, which was 19% lower quarter-on-quarter.

The company’s shares traded at C$0.25 apiece, down C$0.18 when compared with Wednesday. Its share price has fallen by 63.25% since the start of the year.