Silica sand is one of the most common varieties of sand found in the world. It is used for a wide range of applications, and can be purchased from various suppliers throughout the world. Silica sand is used in industrial processing, to make glass, as fill, and to create molds and castings.Silica sand is produced by crushing sand stone or quartzite of open texture, and washing and grading it to yield requisite grain distribution. Silica flour is produced by crushing grinding and washing the high grade quartz, quartzite rocks or from white silica sand.