The mine is situated on the east-west trending Bryngwiog Vein, located west of the Nant Figallt Fault, where Cefn-y-fedw Sandstone and Lower Coal Measures meet Carboniferous Limestone. Evidence of historical workings remains, including a large shaft at SJ 1919 6915, now used as a rubbish dump, surrounded by mine waste and household debris. A second shaft lies further west at SJ 1892 6925. These may correspond to the two engine shafts referenced by Smith (1921), though no structural evidence survives to confirm this.

In the 20th century, the Bryngwiog Mines Company controlled a 265-acre sett south of Moel-y-crio, incorporating much of the former Plas Winter sett along with the Bryngwiog Vein and several other lodes, including Bryngoch, Wern, Fron, and Pantygo.