Barium sulphate is the inorganic compound with the chemical formula BaSO4. It is a white crystalline solid that is odorless and insoluble in water. It occurs as the mineral barite.
Barium sulphate is widely employed as an inorganic filler. Its crystals belong to the rhombic crystal system. The rhombic crystals transforms to monoclinic form at 1148°C and eventually it decomposes to barium oxide, sulfur dioxide and oxygen at temperatures above 1400°C