Organic rock

Anthracite.

Organic rocks are sedimentary rocks formed by deposits of organic origin, ie the remains of living organisms. Typically organic rocks are chalk, charcoal, coral, oil and peat.

A special case is that of limestone, a rock that may appear by chemical precipitation but which is mostly the product of the action of living beings. Calcium carbonate is part of the biological material of most living things. Form your hard parts. The fossilization of these living beings forms limestone. In recent times the importance of Emiliania Huxleyi bacteria in carbon synthesis has been demonstrated, showing how CO2 in the atmosphere is fixed in living beings; and how life has played a decisive role in shaping the atmosphere and the relief of the earth.

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