UPDATE 2-SAfrica Gold Fields, Harmony mines hit by strike

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By James Macharia

JOHANNESBURG, July 16 (Reuters) - South Africa's gold mines owned by Gold Fields (GFIJ.J: Quote, Profile, Research) and Harmony (HARJ.J: Quote, Profile, Research) shut on Wednesday as thousands of mineworkers downed tools in a one-day protest against rising electricity, food and fuel prices.

The strike in the Free State, Northern Cape and Mpumalanga provinces, was part of a drive by the Congress of South African Trade Unions (COSATU) and its allies to pressure the government to limit price increases in Africa's biggest economy.

Wednesday's strike is the second in a string of rolling protests this month, that will culminate in a national strike on Aug. 6, when the country's mines along with other business are expected to grind to a halt in a massive worker stay away.

Gold Fields's Beatrix mine in the Free State province shut two of its three shafts, company spokesman Daniel Thole said.

The mine produces 46 kg (1,624 ounces) of gold per day, but Thole couldn't say how much output would be lost.

Amelia Soares, a spokeswoman for Harmony, said the group's operations in the Free State were "extensively affected". Harmony's Virginia operations, which had been shut down by a safety strike on Tuesday, closed for a second day running.

Losses were estimated at between 30-35 kg of gold per day.