Marble is metamorphosed limestone, composed of fairly pure calcite (a crystalline form of calcium carbonate, CaCO3). It is extensively used for sculpture, as an building material, and in many other applications.

Slate is a fine-grained homogeneous sedimentary rock composed of clay or volcanic ash which has been metamorphosed (foliated) in layers (bedded deposits). Slate can be made into roofing shingles ('roofing slates' in the UK ) because it has two lines of breakability: cleavage and grain. This makes it possible to split slate into thin sheets.