**2. Cementation material**

Cement is a fine and dry powdery substance with major ingredients of calcined lime and clay, the former provides calcium oxide, and the later provides silica, alumina, and iron oxide.

When cement is mixed with water, it hardens into a solid mass. Setting and hardening are caused by hydration, which is a chemical reaction that combines the cement compounds with water to produce microscopic-level crystals or a gel-like material (calcium silicate hydrate) with a high specific surface area. The gel has adhesive properties as well as cohesive forces that can bind other solid materials together [9].
