Graig Ddu Quarry
Graig Ddu Quarry (loc. SH724454) originally opened as Manod Quarry in about 1800, but developed as Graig Ddu in the 1840s. Although output was only about 3000 tons a year (3140 tons in 1882), it reputedly has 36 saw tables and the same number of dressing machines on site. As with others in the area, the quarry suffered from a lack of water, resulting in the siting of the mill some distance away, at a lower level.
This was one of the last quarries to ship slate down the Dwyryd, but after 1865 slate was taken down to Tan y Manod using a new splendid 4 pitch incline. These inclines were renowned for the quarrymen's use of ceir gwyllt (wild cars; singular car gwyllt), a sort of skateboard which sat on one rail, with an arm reaching across to a parallel rail (some photos here), an operation that was only possible at Graig ddu, of all the Blaenau quarries, because the exit incline from the Mill level was both very long and of unusually shallow pitch - it ran across the face of the hillside to the east of Tanymanod, rather than directly up and down.
The opening of the Festiniog And Blaenau Railway in 1868, which connected with the quarry inclines, vastly improved the method of transporting slate from the quarry. When, in 1883, this railway was converted to standard gauge, wagons were carried to Blaenau Ffestiniog using a piggy-back style similar to that used on the Padarn Railway at Dinorwig, after which they were either transferred to the F.R, or into GWR wagons.
The quarry employed 86 men when it closed in 1946. There is a recent (1993) aerial photo of the quarry here. There are more pictures on that site from when it was operational.