Torbanite

Type of fine-grained black oil shale

Torbanite, also known historically as boghead coal or kerosene shale, is a variety of fine-grained black oil shale. It usually occurs as lenticular masses, often associated with deposits of Permian coals. Torbanite is classified as lacustrine type oil shale. A similar mineral, cannel coal, is classified as being a terrestrial form of oil shale, not a lacustrine type.

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