UPDATE 1-South Africa's AMCU union to strike at world's top platinum producers

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RUSTENBURG, South Africa, Jan 19 (Reuters) - South Africa's Association of Mineworkers and Construction Union (AMCU) will strike next week at the world's top three platinum producers, hitting over half of global output and denting the margins of companies struggling to make profits.

AMCU members voted overwhelmingly on Sunday to strike at world no. 1 producer Anglo American Platinum AMSJ.J in a show of hands in a stadium in the platinum belt city of Rustenburg.

In recent days they had voted to strike at Amplats' rivals Lonmin LMI.L and Impala Platinum IMPJ.J .

AMCU president Joseph Mathunjwa told the rally that Amplats would be served notice of the strike action on Monday and workers would down tools on Thursday.

It said last week it would do the same at Lonmin and spokesman Jimmy Gama told Reuters after the mass meeting that Impala Platinum would also get its notice on Monday.

"Comrades, let's intensify the struggle for a better wage," Mathunjwa said to roars of approval from the crowd.

He earlier swept into the stadium in a brand new Lexus car, flanked by three burly white bodyguards, to a rock star welcome and wild cheers from the AMCU members.

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 emissions-capping catalytic converters in automobiles.

(Reporting by Zandi Shabalala and Ed Stoddard; Editing by Tosin Sulaiman and Mark Potter)

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

Keywords: SAFRICA STRIKES/