Silver Standard Inaugurates Pirquitas


Silver Standard Resources’ Pirquitas silver-tin-zinc project in Argentina was recently commissioned and
production was formally inaugurated in early April. Shown here is the mill facility during the late stages of
construction. (Photo courtesy of Silver Standard Resources)
Silver Standard Resources formally inaugurated operations on April 6 at its Pirquitas silver-tin-zinc project in Jujuy province, Argentina. Commissioning had been underway at Pirquitas for several weeks, with first ore delivered to the silver circuit in March. Initial production is based on the processing of more than 400,000 mt of run-ofmine grade jig tails from historic operations, prior to transitioning to processing of ore from the open-pit. As of early March, more than 5 million mt of material had been moved from the Pirquitas open pit and stockpiling of ore had begun.

Silver Standard also reported that, at prevailing metal prices, silver and tin concentrates would account for more than 95% of the anticipated revenue from Pirquitas operations. As a result, the silver circuit is being optimized first, to be followed by the tin circuit. A decision to complete the zinc circuit is dependent on the results of metallurgical test work directed toward increasing silver recoveries and the possibility that process equipment purchased for the zinc circuit might be better used to increase silver recovery.

With production continuing to ramp up through the second quarter, Pirquitas is expected to produce more than 6 million oz of silver in 2009 and to achieve full production of more than 10 million oz/y of silver in 2010.

Total capital expense to develop Pirquitas is now expected to come in at $230 million, up from $220 million estimated in November 2007. Mining, milling and administration costs are expected to average $26/mt over the life of the mine.

Pirquitas is a conventional open-pit operation that utilizes 100-mt trucks and 12-m3 loaders. Ore is trucked 7 km to the processing plant, where it is crushed and treated in a conventional flotation plant. As of November 2007, Pirquitas reserves were estimated at 136 million oz of silver, 113 million lb of tin and 414 million lb of zinc, based on assumed metal prices of $9.35/oz silver, $3.65/lb tin, and $l/lb zinc.

As featured in Womp 2009 Vol 04 - www.womp-int.com