Most people first encounter silica sand during childhood, while playing in sand boxes or at playgrounds. Unlike beach sand, which is mainly derived from limestone, silica sand is made up of quartz crystals, which are found in abundance in earth’s crust. The crystals are extracted by mining and then processed into the various grades of silica sand. Also known as quartz sand or industrial sand, silica sand is an important component for a variety of industrial and construction uses. The use of silica sand is determined by its structure and physical properties. For example, the chemical composition of the silica sand is highly relevant when the silica sand is used in glassmaking, while the grain hardness is an important facet when the sand is used for sandblasting.1
Among the major applications of silica sand are as an abrasive to grind and polish metal, part of the content of building products such as bricks and roofing tiles, in glassmaking, as a refractory agent and as a proppant in the hydraulic fracturing of gas and oil wells. It is also used in the manufacturing of paints, as a filtration material for water and other potable liquid systems and in golf courses, volleyball and other athletic fields.
The characteristics of silica sand that determine its use are cleanliness, (which refers to the ratio of silt, clay and organic matter in any measure of sand); color, (shades of brown or orange indicate the presence of impurities such as iron oxides); as well as grain size, shape, particle size range and refractoriness (melting point).