Made of rock boulders, which is locally available. These boulders are bound together with the help of thin cement mortar (say 1:8). A mould made of steel or wood in the required dimension is used for casting the block. Thin cement concrete may also be used as binder.
Compressive strength 70 kg/cm2
Low water absorption
20% of cost saving when compared to country burnt bricks.
Can be made at site
Cost savings in transportation and loading / unloading