Silica Sand—the most common ingredient in glass. Whether the glass is container glass, window glass, boro-silicate glass, fiberglass or water glass (sodium silicate), silica sand makes up approximately 60-70 percent of the glass batch and therefore has a significant affect on the glass quality.

For all glasses, the consistency of the chemical components and size characteristics are important to producing high quality glass. The three main chemical contaminates in silica sand are usually the iron content expressed as Fe2O3, the alumina content expressed as Al2O3, and Titania expressed as TiO2. If the alumina content is high due to a presence of feldspar, then the other alkalis such as CaO, NaO2 and K2O may also be significant contaminants.

Since silica sand is a low priced commodity, high shipping cost would result in an uneconomical deposit with freight cost being more valuable than that of the silica sand. Thus, it may be necessary to process a lower grade deposit that is closer to the market place than process a higher-grade deposit that is much farther away. Processing can often be achieved at a fraction of the freight cost.