Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rockcomposed of clay or volcanic ash through low-grade regional metamorphism. It is the finest grained foliated metamorphic rock. Foliation may not correspond to the original sedimentary layering, but instead is in planes perpendicular to the direction of metamorphic compression.
For more details, please refer wikipeida https://en.wikipedia.org/wiki/Slate
Profstone provides high quality slate product, black slate and multicolor slate, for material photo, please refer our material page: http://www.profstone.com/?page_id=795
Slate quarry can be found in China Jiangxi, Hebei and Shanxi provinces. It is very solid and easy split into thinner layers. Profstone is applying slate into roofing, paving, walling, gardening and decoration, such as slate chips, dishes etc.