There commonly exist pyrite minerals in coal-bearing strata in one region, but it is difficult to separate.

某地区煤系地层中普遍产出硫铁矿，但非常难选。

youdao

In normal coal samples, quartz and other minerals are found only in trace amounts.

在一般的煤的样板中，石英和其他矿物质的含量是相当低的。

youdao

The distribution of minerals in CWS was analyzed by means of cutting coal into slices in order to investigate the influence of minerals on stability of CWS.

用切片法考察了几种矿物在水煤浆体系中的分布情况，并探讨了矿物对水煤浆稳定性的影响规律。

youdao

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

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