Commercial Grade (Granular)

Calcium sulphate is the inorganic compound with the formula CaSO4 and related hydrates. In the form of γ-anhydrite (the anhydrous form), it is used as a desiccant. One particular hydrate is better known as plaster of Paris, and another occurs naturally as the mineral gypsum. It has many uses in industry. All forms are white solids that are poorly soluble in water. Calcium sulphate causes permanent hardness in water.                                     

CAS  7778-18-9
Molecular Formula  Cas04


Test  Specifications 
Description  Calcium Sulphate occurs as a fine, white to slightly yellow white powder. It is anhydrous or contains two molecules of water of hydration.
Identification  Dissolve about 200 mg of sample by warming it with a mixture of 4 mL of 2.7 N hydrochloric acid and16 mL of water. A white precipitate forms when 5 mL of ammonium oxalate TS is added to 10 mL of the solution.

Upon the addition of barium chloride TS to the remaining 10mL, a white precipitate forms that is insoluble in hydrochloric and nitric acids.

Fluoride  Not more than 0.003% 
Lead  Not more than  2 mg/kg 
Loss in drying  Not more than 1.5 %
Selenium  Not more than 0.003%
Assay  Not less than 98.0% of Cas04
Physical Appearance  White powder match against standard 
pH 1% solution  6.5 – 7.5
Moisture content  2% Max 
Purity  98% Min
Bulk density  0.65 – 0.70 
Sieves test by 325 mesh Free from black particles 
Tile test  Free from black particles 
Storage  Store in cool and dry place 
Packaging  25kg, 50kg