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A group of minerals containing various amounts of the elements Silicon and Oxygen. The Silicates are the largest group of minerals. The construction component of all Silicates is the tetrahedron, which is one Silicon atom equidimensionally placed around four Oxygen atoms.
The silicate minerals make up the great majority of rocks. Silicate is a chemical term for the group of a single atom of silicon surrounded by four atoms of oxygen, or SiO4. They come in the shape of a tetrahedron. Amphiboles are part of the dark (mafic) minerals in igneous and metamorphic rocks.