Thamrin Sihite, director general of minerals and coal at the Indonesian energy ministry, said workers were in the underground training room when the roof collapsed, caving in most of the room.

WSJ: Indonesian Mine Death Toll Rises, Miners Still Trapped

Oh, they would have opened up everything: the metal ores and minerals, the countless deposits of coal.

ECONOMIST: Russia does not exactly soar in its Asian backyard

The company is engaged in exploration for, and mining and sale of coal, copper and other minerals.

FORBES: Strong Buys Among Oil Stocks

Exxon Mobil is engaged in exploration for, and mining and sale of coal, copper and other minerals.

FORBES: Dow Ideas: Dupont, Boeing, Exxon And Chevron

Exports of coal, copper and other minerals from Utah, Wyoming and Montana are beginning to slip because of falling demand in Asia and cut-price competition from Russia and China.

ECONOMIST: The West

There are many types of sulfide minerals, but pyrite and marcasite, the two structural forms of FeS2 that are especially common in coal regions, are the major acid-producers.

FORBES: Fracking With Bad Water

That was the year the government was formulating a draft mining charter, proposing that companies be at least 26% black-owned in order to get a government mining license. (The draft became law in 2005.) Since then Motsepe has diversified, swallowing up or forming partnerships with several other old mining companies and adding a swath of minerals: precious metals (platinum and its cousins), nickel, chrome, iron, manganese and coal.

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