And the experts add that Pori and Stone Rock stones come from volcanic rocks spewed out by volcanoes (the volcano is still actively removing lava) but have differences in the level of violence. Batu Kali Pori is much harder than Stone Mountain. Because of this hardness rate Batu Kali Pori in the Aceh region is often only used as a Building Foundation. Therefore, it is often known as the foundation stone for the building.
While the stone in the saying of mountain rocks in the interest, because it is more easily molded soft usually used as handicrafts such as stone lanterns, Statues, Fountains, Cobek Machine and the like. The level of hardness of Batu Gunung even this varied, there is a bit strong there is soft or even very soft. Almost all buildings use this stone.
So little explanation about the mountain rock.