Summo Minerals revises figures for Lisbon Valley

Lower copper prices have prompted Summo Minerals (SMA-T) to revise the final feasiblity study for its Lisbon Valley copper project in Utah.

The new study, which is based on a copper price of US90 cents per lb., calls for a higher grade of material to be mined at a higher production cost than initially projected.

The new study calculates reserves of 35 million tonnes grading 0.46% copper, compared with an earlier estimate of 46.5 million tonnes grading 0.43%.

The Denver-based company says Lisbon Valley will produce copper at an average cost of US47 cents per lb. for a minimum mine life of eight years.

The original feasibility study, released in September 1995, predicted an 11-year mine life.

“In a nutshell, we’ve cut three years off the life of the mine and reduced the tonnage,” says Clive Massey, a Summo spokesman. “Even at today’s copper prices, and lower, we are still profitable.”

The stripping ratio is now calculated at 1.84-to-1, compared with the earlier estimate of 2.36-to-1.

Capital costs were previously estimated at US$46 million but are now pegged at US$42 million (not including working capital and financing fees).