PERU – GOLD HAWK RESOURCES of Vancouver has begun mining and concentrator operations at its Coricancha mine. A full production level of 600 t/d at the mill should be achieved during June 2007. The project in the central Andes was formerly known as Tamboraque and has been exploited almost continuously since colonial times.
Gold Hawk said it had to begin mining with rented equipment due to the delayed delivery of the mining equipment that it ordered. The new equipment is expected in July. The company expects to produce 11,000 oz of gold, 400,000 oz of silver, 4.8 million lb of zinc and 4.3 million lb of lead in 2007. Those levels are down 20-25% from earlier expectations due to startup delays.
At the mill additional conditioning tanks, thickeners and flotation capacity have been installed. Other modifications include a heating system to raise the pulp temperature of the pyrite/arsenopyrite concentrate, which tests have shown will improve gold recoveries. In addition, a fines handling system has been installed in the underground ore handling system, which will reduce the effects of dilution.
The installation of the lead flash flotation cell is also underway and should be completed in the second half of June. The flash cell facilitates the removal of coarse lead particles before they have an opportunity to be over-ground in the grinding circuit. This improves the subsequent differential flotation of other concentrates and results in an overall improvement in concentrate grades, according to the company.
The dense media separator (DMS) originally scheduled to be done at the end of June will be delayed until September due to the late delivery of the two main pumps and magnetic separator. When fully operational, the DMS plant will result in higher grade ore reporting to the mill, and in general will also result in lower operating costs due to electricity savings. However, the greatest benefit from the DMS plant will be that a higher feed rate at a higher grade can be sent to the mill, without increasing the capacity of the mill.
The production of lead and zinc concentrates has begun with the first shipment delivered on May 4, 2007, said Gold Hawk. Since then, production and shipments have been steadily increasing. The Biox circuit is in operation with Biox product now flowing to the cyanidation circuit, where gold and silver is being adsorbed onto carbon. Preliminary results suggest that performance is meeting designed gold recovery. A small gold bar has been poured as a test of the systems and it is anticipated that carbon loading will be sufficiently advanced so that the first full gold pour will occur in early June.
Additional information and a few photos are posted at www.GoldHawkResources.com.