Natural glass has existed since the dawn of time. It is formed when certain types of rocks melt as a result of high-temperature phenomena such as volcanic eruptions, lightning strikes or the impact of meteorites, and then cool and solidify rapidly.
Today we can subdivide the glass market into three segments:
- Flat glass
- Container glass (hollow glass)
- Fiber glass
Calcium carbonate is used in glass as a stabilizer, and modifies the viscosity and increases the durability of the glass. For all types of glass, the common properties required of calcium carbonate are extremely low iron content, consistent chemical characteristics and low moisture content. Dolomite, a magnesium calcium carbonate mineral, can also be used as a stabilizer to improve the resistance of glass to natural or chemical attack in all three types of glass.
The ceramic market can be divided in two major segments – ceramic glass bodies and porous ceramic tiles.
Besides silica sand, calcium carbonate is another main component in the production of ceramics. Calcium carbonate is an economical source of calcium oxide, which is needed as a melting agent at high temperatures (1,050 °C), improves the mechanical and chemical strength of the glass body and reduces shrinkage from firing.