Twin headed back to Atlanta

With gold prices remaining above US$300 per oz., Twin Mining (TWG-T) plans on revisiting its roots and revitalizing its 81.3%-owned Atlanta gold project near Boise, Idaho.

At last count, Atlanta’s measured and indicated resources stood at 18 million tonnes grading 1.9 grams gold and 5.6 grams silver per tonne. The resource is contained in two surface mineable deposits – the Monarch and Idaho pits. A 1997 prefeasibility study by Behre Dolbear pegged proven and probable reserves in the two pits at 11.2 million running tonnes 2.1 grams, based on a mining dilution factor of 6% and a mine recovery factor of 95%.

The deposits are situated in the Atlanta Shear, a 3.7-km-long shear zone that cuts through biotite-granodiorite country rock. Gold and silver are associated with quartz veins and the surrounding, hydrothermally altered granodiorite.

Plans at Atlanta call for an updated environmental impact study. The company also intends to sink about 2,000 metres of large-diameter holes aimed at collecting enough ore to for a program of independent gold leach tests. A bankable feasibility study for a conventional cyanide-heap-leach gold operation will follow.

An updated scoping study in 1999 envisaged a production rate of 78,000 oz. per year with a recovery rate of 62.3%. Over a six-year mine life, production would tally to 469,000 oz. at an average cash cost of US$165 per oz. Capital cost are pegged at US$31.2 million. The operation’s net present value at a 5% discount is US$22 million; the internal rate of return is 20.3%.

Poor recoveries and a slumping gold price forced the project to be shelved in the late 1990s. It remained on care and maintenance since. A similar fate befell the 85%-held Layuh property in South Kalimantan, Indonesia.

The company plans on debt-financing construction at Atlanta.

The property covers 7.5 sq. km of mineral rights and includes several former gold producers, which produced about 400,000 oz. of gold and 900,000 oz. of silver between 1864 and 1960.