Marble is a carbonatic rock of metamorphic origin and some ophiolitic rocks [serpentinites and ophicalcites], formed by the alteration of limestone or dolomite, often streaked.

Granite rocks are igneous rocks, which were formed by slowly cooling pockets of magma that were trapped beneath the earth's surface.

Sandstone rocks are sedimentary rocks made from small grains of the minerals quartz and feldspar. They often form in layers as seen in this picture.

Slate is a metamorphic rock which is impermeable, hard, close in texture, quick drying, frost resistant, fine grained and fissile - ie it splits easily into thin layers.