Oxus Revises Amantaytau Planning

Oxus Gold, owner of a 50% interest in gold and silver producer Amantaytau Goldfields in Uzbekistan, has downsized plans for development of an underground sulphide mine at its Amantaytau operations. The new plan calls for investment of $74 million to develop a 450,000 mt/y underground mine producing about 100,000 oz/y. Previous planning, based on a June 2008 feasibility study, assumed investment of $170 million to mine 750,000 mt/y (increasing to 1.2 million mt/y) and produce as much as 270,000 oz/y of gold. Commissioning of the downsized sulphide plant is expected in the first quarter of 2011. Amantaytau surface oxide mining operations produced 66,465 oz of gold in 2008, down from 83,339 oz in 2007.

Oxus attributed the Amantaytau planning change to the current economic climate, which has resulted in a delay in raising capital needed to develop the underground sulphide mine. The revised project will exploit a reserve of 911,000 oz of gold within a measured and indicated resource of 1.9 million oz over a life of 12 years.

Oxus expects to enter into a mining contract with Shaft Sinkers Ltd. by November 2009 for underground mine development. The underground mine will be accessed via a single decline, with the existing No. 10 Shaft being utilized for ventilation and as a second route of egress. Mine design is planned around transverse bench-and-fill, longitudinal-retreat stoping and a reduced amount of cut-and-fill stoping in comparison with the original feasibility study.

The Amantaytau sulfide ore will be processed using bio-oxidation technology provided by Gold Fields Ltd. The existing carbon-in-pulp plant will be modified to accept the sulphide ore. The existing milling, reagent handling, elution, electrowinning, and smelting sections will be retained and upgraded, while the leach feed thickener will be converted to accept flotation tails. The float concentrate will be bio-digested to break down the sulphide minerals, thickened, and cyanide leached in a carbon-in-leach section. The plant will be constructed initially to treat 450,000 mt/y using only one of the existing mills and a single bio-oxidation module.

As featured in Womp 2009 Vol 05 - www.womp-int.com