JOHANNESBURG, March 2 (Reuters) - South Africa's Solidarity union on Wednesday said it had accepted miner Sibanye-Stillwater's final wage offer and withdrawn from any further organized labor action, splitting from a group of unions negotiating together for the first time.

Solidarity, along with three other unions, had been negotiating since December over wages at Sibanye's South African gold mines but said it did not take part in a union strike vote on Tuesday after deciding to accept the offer.

Under Sibanye's final offer - the sixth since talks began - miners, artisans and officials would receive a 5% pay increase each year and "unskilled and semi-skilled" employees would be given an increase of 800 rand ($51.72) a month for each of the three years, including a 100 rand a month increase in allowances.

Solidarity said that an "overwhelming" majority of its members accepted the final offer in a confidential vote.

"We are satisfied with the offer and are happy that we could negotiate this increase for our members," Riaan Visser, deputy general secretary at Solidarity, said in a statement.

The remaining unions in the coalition - the Association of Mineworkers and Construction Union (AMCU), National Union of Mineworkers (NUM) and UASA - have yet to announce the result of Tuesday's vote on whether to strike.

A Sibanye spokesperson declined to comment on Solidarity's decision, saying the company is awaiting the outcome of the ballot process. ($1 = 15.4676 rand) (Reporting by Helen Reid Editing by Jane Merriman and David Goodman)