The vibrant colors and unique texture makes slates appropriate for interior as well as exterior applications. Slate is formed of compressed layers of sediments formed under ocean. Slate is a regionally metamorphosized, argillaceous rock, that has developed but has suffered re-crystallization, and compressed into a dense stone made up of quartz, iolite, mica and calcite. Because it is formed in layers, it can easily be split to expose beautifully textured surfaces. The usual colors of slates are earthy (various shades and mixes of browns, beiges, yellows), black, dark-grays, and greenish-gray but shades of pinks, purples and copper are also found. They usually exhibit lot of variations among the pieces quarried from the same pit. Slates, depending on their individual hardness, are used for flooring, cladding and landscaping.