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The mineral kingdom consists of the fossil substances found in the earth. These are either entirely destitute of organic structure, or, having once possessed it, possess it no longer: such are the petrefactions.

William Withering, Torbern Bergman (1822). “The miscellaneous tracts of the late William Withering: to which is prefixed a memoir of his life, character, and writings”, p.9
The mineral kingdom consists of the fossil substances found in the earth. These are either entirely destitute of organic structure, or, having once possessed it, possess it no longer: such are the petrefactions.