... plaster stone or phosphogypsum, sulphur trioxide content, ≥35%. (3). Aluminium powder: activated aluminium content, ≥90%.(4). Cement: 32.5R bulk cement. (5 ... ). Proportion: cement, 8%; Quicklime, 19%; sand, 70%; Gypsum, 3%; aluminium powder, 450g/m3; addictives: 400g/m3. (3). Each mould products: 4 ...