naturally occurring substances

Minerals

Minerals Minerals are defined as solid, inorganic, naturally occurring substances with a definite chemical formula and general structure. Almost all chemical elements in the Earth’s crust are associated with at least one mineral. They vary in color, hardness, density, crystal form, crystal size, transparency, composition, location, and abundance. Some minerals are radioactive (uranophane), while others … Read more

Ore

Ore An ore is a special type of rock that contains a large enough amount of a particular mineral (usually a metal) to make it economically practical to extract that mineral from the surrounding rock. Not all minerals are found in a large enough amount in one location to make it worth it to remove the ore … Read more

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