Slate is a very fine grained metamorphic rock derived from the sedimentary rock 'shale'. Slate is composed mostly of mica, chlorite and quartz.
Slate is impermeable, hard, close in texture, quick drying, frost resistant, fine grained and fissile – i.e. it splits easily into thin layers. It is brittle and needs to be handled carefully. Slate has an excellent shining property. Slate is a popular ornamental and decorative stone because of the pleasing colors, attractive patterns and designs.