1. n. [Geology]
[SiO2]
An abundant rock-forming mineral composed of silicon and oxygen, also called silica. Quartz sand grains are a major constituent of sandstone and other clastic sedimentary rocks.
See related terms: authigenic, chert, felsic, granite, hydrothermal, hydrothermal alteration, igneous, mineral, rock, sand, sandstone, sedimentary, silica, silicate mineral