Question

Which of the following is not an ingredient of clinker?

• A. Calcium silicate
• B. Aluminium silicate
• C. Calcium aluminium silicate
• D. Gypsum

Answer 1

The correct option is D Gypsum

In the manufacture of Portland cement, clinker occurs as lumps or nodules, usually $3mm\left(0.12in\right)$ to $25mm\left(0.98in\right)$ in diameter, produced by sintering (fused together without melting to the point of liquefaction) limestone and alumino-silicate materials such as clay during the cement kiln stage. Gypsum is not present in it.