The quarry opened in the 1860s and was initially worked into the hillside on an outcrop of the Nod Glas Formation.

In 1876, Blackwell contracted Issac Hughes of Rhyl to build a large reservoir in the hills above the quarry.

A water turbine was installed at the mill before 1880, a notably early date for equipment of this sort in the Welsh slate industry.

[3] Carnarvonshire Council denied the quarry's application to build a tramway across the road, on a level crossing;[10] this may have been the reason for the incline's abandonment.

Finished product from the mill was carted across the river to Pont-y-Pant railway station over a fine slate and timber bridge.