Slate

Geology lesson:

Slates are made up of tiny particles built up into layers of clay several hundred feet thick. Later volcanic reaction created folds in the earth's crust, heaving new mountains out of the seabed, with the accompanying compression and movement making all the particles lie in the same direction. Heat from the intrusion of volcanic gasses and lavas caused some of the original mineral particles to make new chemical combinations, especially minute flat ribbon-like particles of mica.....



Usage:

Roof, batu nesan, pavement, decoration etc....