Certain gemstones are formed by magma, a material found deep inside the Earth, that has pushed toward the surface and solidified; others are created when superheated water and gases cool. When chemical action, heat, or pressure changes the existing structure of rocks, they may recrystallize to form gemstones such as emeralds. A large chemical company plans to create a new source of profits by applying certain of the chemicals it manufactures to specifically chosen rock samples, which would be a
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