Ions form when atoms gain or lose neutrons. Isotopes of the same element have different mass numbers. The elements silicon and carbon comprise nearly three-fourths of Earth's continental crust. Quartz is the mineral from which plaster and other similar building materials are composed. Luster is the external expression of a mineral's internal orderly arrangement of atoms.
Uncombined atoms have the same number of neutrons as protons.
The structure of the silicon-oxygen tetrahedron consists of four oxygen atoms surrounding a smaller silicon atom. Vitreous, pearly, and silky are types of metallic lusters. Reserves are already-identified mineral deposits from which minerals can be extracted profitably. A mineral is a naturally occurring inorganic solid that possesses a definite chemical structure. Oxides, sulfides, and carbonates are common nonsilicate mineral groups.