Quartz grains are small pieces of quartz, a mineral composed of silica and oxygen atoms. Quartz grains are found in a variety of sizes, ranging from microscopic to boulder-sized. They are used in a variety of industrial and commercial applications, including glassmaking, abrasives, and filtration. Quartz grains can also be used as an aggregate in concrete and asphalt mixtures. Quartz grains are also used as an additive in pottery glazes, as a filler in paint and varnish, and as an abrasive in soaps and cosmetics.