In 1956, while digging in the soil in the Crater of Diamonds in Arkansas, a woman from Dallas found a 15-carat diamond. She found a type of __________.

A diamond is a naturally occurring solid with a definite chemical composition and crystal structure, so it is classified as a mineral. It is not a fossil fuel or petroleum, which form from ancient organic matter, and it is not a renewable resource. The correct choice is mineral.

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