UPDATE 1-S.Africa's AMCU union to strike at Lonmin next week

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JOHANNESBURG, Jan 16 (Reuters) - South Africa's Association of Mineworkers and Construction Union (AMCU) said on Thursday its members had voted in favour of a strike over wages at world No. 3 platinum producer Lonmin LMI.L and they would down tools next week.

"On Monday the management at Lonmin will be served with a 48-hour strike notice," Evans Ramokga, an AMCU activist on the platinum belt, told Reuters.

AMCU members have voted in favour of a stoppage at Impala Platinum IMPJ.J over wages, and the union will canvas its rank and file at the world's top producer Anglo American Platinum

AMSJ.J on Sunday at a mass rally in the platinum mining town of Rustenburg.

The three are the world's top producers of the precious metal and account for more than half of global output.

A simultaneous stoppage at all three would hit a key South African export at a time when the rand currency is near five-year lows and deal a fresh blow to investor confidence in the continent's biggest economy.

Ramokga said it was possible that Amplats and Implats would also be served with 48 hour strike notices - a legal requirement in South Africa - on Monday.

At Amplats and Lonmin, the union is seeking a minimum monthly wage of 12,500 rand ($1,200) for entry-level workers - more than double current levels, under the populist battle cry of a "living wage". At Implats the union scaled back its demand late last year to just over 8,500 rand.

Companies have said they can ill afford steep increases as power and other costs soar against the backdrop of depressed prices for the white metal used in jewellery and emissions-capping catalytic converters in automobiles.

(Reporting by Ed Stoddard; Editing by David Evans)

((Edward.Stoddard@thomsonreuters.com)(+27 11 775 3160)(Reuters Messaging: edward.stoddard.thomsonreuters.com@reuters.net))

Keywords: LONMIN STRIKE/