Granite: Granite crystallizes from magma that cools slowly, deep below the earth’s surface. Exceptionally slow rates of cooling give rise to a very coarse-grained variety called pegmatite. Granite used to identify a group of minerals that often contains Quartz, Feldspar, Plagioclase, etc and is igneous (or seem to be) in origin. Usually have darker colors. Contains very little calcite, if any. Provides a heavy crystalline and granular appearance with mineral grains. It is very hard material and easier to maintain than marble. It is still porous and will stain.There are different types of granite depending on the percentage mix of quartz, mica and feldspar
formations and grain formation changes. One or a combination of these characteristics will affect the texture. Limestone has a smooth granular surface. Varies in hardness. Some dense limestone can be polished. Common colors are black, grey, white, yellow or brown. Limestone is known to contain lime from seawater.
A recrystallized limestone that formed when the limestone softened from heat and pressure and recrystallized into Marble where mineral changes occurred. The main consistency is calcium and dolomite. Ranges in many colors and is usually heavily veined and shows lots of grains.
The shale from which slate originate were deposited previously on clay beds. Subsequent earth movements tilted these beds of shale, at first horizontal, and the intense metamorphism that converted these into slates folded and contracted them. Slate a fine-grained stone that formed from clay, rock shale, and sometimes quartz. They are very thin which can break easily and usually black, grey, or green.