South Africa's NUM says coal strike to begin on Nov. 19

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JOHANNESBURG, Nov 10 (Reuters) - South Africa's National Union of Mineworkers will begin a strike over wages in the coal sector on November 19, the union's spokesman said on Friday.

A protracted strike in the coal sector could affect power supply in Africa's most industrialised economy, as about 85 percent of electricity is generated from the fossil fuel.

According to the Chamber of Mines, the companies involved in the negotiations, which include Anglo Coal, Delmas Coal, Exxaro, and Glencore (Frankfurt: 8GC.F - news) , account for about half of South Africa's coal production and employ 14,000 people, 20 percent of the labour force in the sector.

NUM represents about 70 percent of these employees, the chamber said.

The two sides are not far apart. The larger companies have offered a staggered increase of 1100 rand ($76) for year one for lower-paid employees, and an increase of 7.5 percent for the higher categories.

The smaller companies have offered increases ranging from 5 to 7.5 percent. The union has been demanding a once-off payment of 1,100 rand this year and an 8 percent increase for 2018.

South Africa is also a major coal exporter.

The volumes of South African coal destined for export markets delivered by rail to port increased 6.5 percent to 37.8 million tonnes in the six months to the end of September, state-run logistics group Transnet said last week.

($1 = 14.3879 rand) (Reporting by Ed Stoddard; Editing by Joe Brock)