Minerals are crystalline solids that can either be an element or a compound, that were formed through natural process, like: crystallization, volcanic activitiy and movements of tectonic plates.
When an atom of silicon bonds with four atoms of oxygen, it forms the building blocks of silicate minerals, which is also called a tetrahedron. Quartz and feldspar are the two most common silicate minerals. Emerald, a gem stone which is a type of Beryl, is also a silicate mineral.