Slab Mill

Cadw's description

Location

Directly adjoins the large slate mill on Level IV (Bonc Isa') of Pen-yr-Orsedd Slate Quarry.

History

Built in 1868 housing a new steam engine, a Hunter patent saw costing £200 and a 9' by 5' (2.74m by 1.5m) planer costing £100. The planer is now in the slate mill on Level VI of the quarry. The quarry opened c1816 when it was worked by William Turner. In 1863 it was bought by W A Darbishire & Co., after which it underwent substantial modernisation, reflected in the use of both water and steam power. During the 1890s about 450 men worked here; it finally closed in 1997.

Exterior

Large rectangular plan structure adjoining the south-east end of the even larger slate mill to the north. Built of regularly coursed slate slabs under a low-eaved gable-ended slate roof.

Interior

Contains a smithing hearth and a crusher base.

Reason for designation

Included as a well-preserved slab mill, important for illustrating the experimental stage of mechanical slab processing at Pen-yr -Orsedd and as part of the remarkably well-preserved complex of slate quarry structures on the site. It is the earliest surviving mill in the whole of the Dyffryn Nantlle area.