Answer:
Silica.
Explanation:
The mass of the earths crust is 59 percent Silica. Silica, SiO2, is composed of Silicone and Oxygen. It has been known since ancient times, is found in sand, and is a major component of glass. Silica is a chemical compound, also called silicon dioxide.
In sand, this silica usually exists in the form of quartz. Quartz has a chemical formula of SiO2 and adopts a crystal structure where every silicon atom is attached to four oxygen atoms and every oxygen atom is attached to two silicon atoms. In some countries, sand is also made up of calcium carbonate. The chemical formula for calcium carbonate is CaCO3.
