May 16, 2011 12:04 PM EDT African Barrick Gold (ABGL.L) said a malfunction in a mill motor at its Buzwagi mine in Tanzania would hit production in the quarter, sending its shares down as much as 9 percent in early trade on Monday. It estimated the replacement of the motor, which failed after a power outage and attempted restart, would take two weeks, during which time the plant would run at reduced capacity. The miner, a unit of the world's largest gold miner Barrick Gold Corp (ABX.TO), estimated the production impact at around 10,000 ounces of gold, though it said it would recover most of that in the second half of the year and confirmed full-year production expectations for Buzwagi. At 0735 GMT the stock was down 3.8 percent at 479.5 pence, recovering from an earlier low of 455.2 pence, but still underperforming a 0.7 percent rise in the broader mining index. African Barrick expects to produce between 700,000 and 760,000 ounces of gold this year compared with around 701,000 ounces in 2010. Buzwagi is Tanzania's second-largest mining operation. African Barrick said it would continue to work with the country's state power utility to improve the reliability of power supply to the mine.