Silicates

Silicates are made up of silicate
ions, which are formed by four oxygen ions (O2-) surrounding and
sharing electrons with a silicon ion (Si4+). Silicates can be combined
with metals. The best known silicate mineral is quartz which is made up of one
atom of silicon and two atoms of oxygen (SiO4)4-.
Silicates are the largest naturally occurring mineral on the earth and make up about 95% of the earth's crust.