High Alumina Cement (HAC), sometimes known as calcium aluminate Cement (CAC) or Alumina Cement, is composed of calcium aluminates, unlike Portland Cement which is composed of calcium silicates. It is manufactured from limestone or chalk and bauxite.

The characteristics of this cement can be surfacely summarized in following points:

• High alumina cement has low PH
• It has high refractoriness
• It has high durability in sulphuric acid
• It hardens rapidly
• It is less reactant than alumina or hydraulic lime
• It acts as a bonding material when added in refractory castables because it forms ceramic bond at high temperatures
• It has high resistance to chemical corrosion. So, it is widely used also in construction of water pipes, sewage pipes, factory drains, coastal constructions and in factory chimneys.