5000 years ago, on a beach in the Middle East, some people started a fire, and later found in the sand, some of the transparent beads, like jewelry. How did this novelty change to become a household necessity and the main building material in twentieth Century?
The manufacture of glass raw material, silica is the most abundant reserves of underground minerals. Many rocks such as granite contain white silica. Around the beach is the water from the smash rocks and sand is the main source of silica.
Go to the beach, scooped up a handful of sand a closer look, in addition to black, red, yellow and other colors clear particles, some translucent that silica. There are other minerals in the sand, but in most silica. Silica is hard, insoluble in water, does not decompose, longer than other minerals retained.
The chemical composition of the white sand is silicon, which is made of this sand, which is called silica glass, which is heat resistant and transparent.
The melting point of pure silica is very high, if adding soda (sodium compound), it will reduce the melting point of many.
Today, with lime and soda ash and silica mixed glass factory for raw materials, production of sodium calcium glass for glass bottle, a pane of glass and cheap glass production. Ordinary glass composition, silicon accounted for 60% ~ 70%, 15% ~ 25%, sodium lime accounted for 5% ~ 10%.