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In addition, it must be hard and durable. Its value increases if it is also rare.The beauty of a gem is measured in terms of its clarity, brilliance, and color. Comments
However, some minerals, such as diamonds, can be manufactured by humans. Diamonds are nevertheless classified as minerals, because they adhere to the five core characteristics of minerals. In addition to being formed by a natural process, minerals are stable at room temperature. This simply means that all minerals are solid at normal temperatures and pressures common on the Earthâs surface. This characteristic excludes water from being a mineral because of its liquid state but includes the solid form of water â ice â as a valid mineral. Minerals are also represented by a chemical composition or atomic structure.