an oxide of a nonmetal formed when a nonmetal burns.

a white mineral consisting of silica; found in volcanic rocks

a hard glossy mineral consisting of silicon dioxide in crystal form; present in most rocks (especially sandstone and granite); yellow sand is quartz with iron oxide impurities

colorless glass made of almost pure silica

a mineral form of silica

sand that is mainly composed of quartz, used as the main raw material for commercial glass production.

variety of silica containing microcrystalline quartz

a hard kind of stone; a form of silica more opaque than chalcedony

a pure form of finely ground silica

a white mineral consisting of silica; found in volcanic rocks

a hard glossy mineral consisting of silicon dioxide in crystal form; present in most rocks (especially sandstone and granite); yellow sand is quartz with iron oxide impurities

colorless glass made of almost pure silica

a mineral form of silica

sand that is mainly composed of quartz, used as the main raw material for commercial glass production.