Genshoseki (Miyagi Prefecture) [Famous Japanese Stones]

Black Slate

Gensho stone

Gensho stone is a thin layered slate.
Its history is long, dating back to the Muromachi period.
It is produced in Miyagi Prefecture, famous for the Sengoku period warlord Date Masamune, known as the One-Eyed Dragon, and is mainly mined in Tome City and Ishinomaki City.
It is believed that clay and mud deposited in the Late Permian period were deposited by underwater action, and that layered cleavage was formed by crustal movements that occurred in the Early Cretaceous period.
The black component is made up of carbon and is layered, so it peels off in thin layers. However, it is also resistant to chemicals, seasonal and weather changes, and does not absorb water or get dirty easily, so it is sometimes used as a roofing material.

Gensho stone (type of slate from Miyagi pref.) is a thin layered clay rock. Its history is old and dates back to the Muromachi period. The production area is from Miyagi prefecture, which is famous for Date Masamune, a military commander during the Sengoku period. It is mainly produced in Tome City and Ishinomaki City. It is said that clay and mud which accumulated in the late Permian period was deposited by the movement of water and tectonic movements that occurred in the early Cretaceous period, formed stratified cleavage.
The black component of the stone consists of carbon and can be peeled away because of their thin layers. They are used as a roofing material due to the resistance to chemicals, seasonal changes and climate changes. Furthermore it hardly absorb any water and don`t get dirty easily.