most of the buildings are, nowadays, constructed using concrete bricks. earlier clay bricks used but availability of clay is bit hard.

manufacturing process:

the big rocks from mountain is crushed into small size in a crusher. It is then transported to the work site. there it is mixed with sand and cement to make concrete. this is done in an concrete-mixture-machine. then it is shaped into brick with help of an electric power press.

if we analyze the manufacturing process, we can see that lot of energy spent in all the way.