Gypsum
It is a hydrated calcium sulphate (CaSO4.2H2O) the proportion of chemically combined water being 20.0%. Generally it occurs in six recognized forms. Gypsum is widely used in industry because of its special property of losing three fourth of the combined water of crystallisation when moderately heated (Calcining) of about 130°C. Beside, this 'calcined gypsum' when cooled, finely ground and made plastic with water can be spread out, cast or mould to any desired surface or form, and finally can resume its original state or set into a hard rock like form.
Key Specifications
| Purity | 90-96% Min |
|---|---|
| Free Moisture | 3% Max |
| Combined Water | 19% Min |
| CaO | 32% Min |
| SO3 | 45% Min |