Slate
- Alternate meanings in Slate (disambiguation)
Slate is a fine-grained homogeneous
sedimentary rock composed of
clay or
volcanic ash which has been
metamorphosed (foliated) so as to develop a high degree of fissility or slaty cleavage which is usually at a high angle to the planes of stratification. This high degree of fissility makes the better grades of slates an extremely useful roofing material (although its use has fallen in favor of synthetic and manufactured substitutes). Some of the finest slates in the world come from
Wales in the
United Kingdom.
See also: List of minerals