Fortune Minerals Ltd. reported Dec. 4 the startup of a $3.8 million pilot plant last month at SGS Lakefield Research Limited in Ontario for its Nico cobalt-gold-bismuth deposit in the Northwest Territories.
Fortune aims to confirm the economic feasibility of producing precious and base metals from NICO. A total of 180 metric tons of ore mined from the Nico deposit during the 2006 and 2007 underground test mining programs will be processed by May, the company said.
Underground mining tests conducted at Nico produced about 6,000 metric tons of ore from two levels of the deposits and 100,000 metric tons of waste development rock from an access ramp and raises. Two composite samples were taken from the ore for the pilot to simulate average operating conditions for the mine. A number of subcomposites also were taken to represent the variability of ore grades expected during mine operations and will be used to test this variability.
Fortune said preliminary results of bench-scale flotation tests of the bulk sample and also from 10-hour pilot plant runs for the flotation phase of the Nico pilot plant have been encouraging.
Gold-bearing cobalt and bismuth concentrates produced during the flotation stage of the Nico pilot plant this year will be used to complete the hydrometallurgical components of the test in January through May. These scheduled hydrometallurgical components include: cyanide recovery of gold from bismuth and recovery of bismuth by ferric chloride leaching and cementation onto iron by February; pressure acid leaching, ion exchange purification and electro-winning of cobalt to cathode in March and April; and cyanidation of the cleaner float tails and autoclave residue in April and May.
A primary consideration for the schedule and sample delivery was the availability of the pilot-scale autoclave at SGS Lakefield, which Fortune has reserved for March and April.
Nico, about 160 kilometers, or 99 miles, northwest of Yellowknife, is targeted for production in 2010. A feasibility study identified reserves in the deposit of 21.8 million metric tons, containing 61 million pounds of cobalt, 760,000 ounces of gold and 77 million pounds of bismuth within a larger lower-grade resource. Fortune aims to develop Nico using a combination of open pit and underground mining with a process plant to produce cobalt cathode, gold doré and bismuth cement or metal.