Are there different types of portland cement ?

• Through all portland cement is basically the same , eight types of cement are manufactured to meet different physical and chemical requirements for specific applications :

1. Type I is a general purpose portland cement suitable for most uses . 
2. Type II is used for structures in water or soil containing moderate amounts of sulfate , or when heat build-up is concern . 
3. Type III cement provides high strength at an early state , usually in a week or less . 
4. Type IV moderates heat generated by hydration that is used for massive concrete structures such as dams . 
5. Types V cement resists chemical attack by soil and water high in sulfates . 
6. Types IA , IIA and IIIA are cements used to make air-entrained concrete . THey have the same properties as types I , II , and III , except that they have small quantities of air entrained materials combined with them . 

White portland cement is made from raw materials containing little or no iron or manganese , the substances that give conventional cement its gray colour .