Coity Quarry dates from the 1830s and was first shown on the 1844 Tithe map. The quarry was worked for building stone by the Blaenavon Iron & Coal Co. It presumably became disused by the 1880s when a coal level (NPRN 67796) had been driven into the base and an air shaft had been sunk (NPRN 67673).

It os a large quarry with a 30 metre high exposed face in an arc approximately 70 metre east to west. There is scree at the base and large conical spoil tips to each side up to 30 metres high. Stone was taken down an inclined tramroad, running more or less through the existing Big Pit site. At the incline head, inside the quarry, there is a large (approximately 2.5 metres diameter) braking drum for balanced working. This is in a good state of preservation.

Claire Parry, RCAHMW, 26 July 2011.

Source:
R Hayman, Hayman & Horton, 8/1/2003
A Guide to the Industrial Archaeology of South East Wales, AIA, 2003