Nevsun shares plunge 30% after slashing 2012 guidance

Shares in Nevun Resources Ltd. fell off the cliff this morning after the company issued a press release saying its 2012 production estimate from its Bisha copper-gold mine in Eritrea is half of what the mine produced in 2011.

The shares crashed around 30% , the biggest intraday drop since October 2008, after Vancouver-based Nevsun issued production guidance of 190-210,000 ounces, compared to the 379,000 ounces pulled from the mine last year.

Bloomberg reported the company saying its March 2011 estimate of its resources was too optimistic, and it will delay its revision of  estimates for the entire project to the second or third quarter from the originally scheduled first quarter.

The company's shares soared 22% when it reported a copper discovery next to the mine back in October, Bloomberg said.

Nevsun said it is expecting to begin copper production in 2013.