Dolomite in Glass Industry
High-grade dolomite with as low Iron and Silica content as possible is required by the glass industry. Glass grade dolomite is typified by its purity and consistency. Dolomite is a double carbonate of calcium and magnesium (CaCO3, MgCO3). The chief undesirable impurities are iron followed by chromite, manganese, vanadium and lead, all of which may cause defects in the float glass or color glass. For certain commercial colourless glass the Fe2O3 content up to 0.25% is permissible, but for pure colourless glass, Fe2O3 content of 0.04% (max) is sometimes specified.
Requirement of High-grade dolomite for Glass :
- For certain commercial glass, the Fe2O3 content up to 0.25% is permissible.
- For truly colorless glass Fe2O3 content of 0.04% (max.) is sometimes in specification.
- High degree of whiteness
- Low moisture content
- Environment friendly
- Slow reaction with acids
- High magnesium content
- High density