Claudy Schist

Claudy schist is not technically a schist but a metamorphosed quartz-rich sandstone or psammite which formed during the Dalradian (1000-545 million years ago). It is distinctly different from Derry Schist being orange or rusty brown in colour due to the presence of iron oxide.

It has a courser granular texture and can have bands of grey or black pelite (metamorphosed mudstone) or clasts of quartz and feldspar. It has been used extensively in the Claudy area and throughout counties Londonderry and Tyrone.