The leaves of ferns, reeds, and other plants, are frequently found between layers of shale or slaty clay, beautifully perfect, but converted into coal.

我们通常能在页岩层和黏板岩层中发现蕨类植物，芦苇和其它植物的叶子，但是这些叶子都完全转变为了煤。

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Company production brick machine products are applicable to shale, gangue, coal ash, clay as material of brick making users.

公司生产的砖机产品适用于以页岩，煤矸石，粉煤灰，粘土等为原料的制砖用户。

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The interaction of paraffin wax emulsions with clay dispersions was investigated with respect to size distribution, shale recovery, line swelling and lubrication properties.

通过对粒度分布、页岩滚动回收率、线性膨胀和润滑性的测定，研究了石蜡微小乳状液与黏土分散体系的相互作用。

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The council said two companies were applying to Mendip district council for permission to test drill for the gas, which is found in shale formed from deposits of mud, silt, clay and organic matter.

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