The main processing works for the Berth-lwyd gold mine in the C19th until the lease ran out and the works was re-established up the hill at Cefn Coch (NPRN 33962). The principal remains here are the large mill, with working floors on several levels partly obscured now by trees, but otherwise well preserved. The features include two water-wheel pits at the S end of one there is an "edge-runner" a type of powered grinding device and a unique feature of the Welsh goldmines. The circular lower stone of this was 3.6m in diameter with two segments of the stone surviving; one in situ and one upsidedown on the terrace below. This was driven by a steam engine in the late stages of the mill's operation (around 1860). One other notable feature is a large round buddle or settling tank and several other less well defined structures as well as some evidence of early prospecting for ore in the field to the immediate S of the site. The main are of ore extraction was finally established to the S of the site and consists of one long line of adits, and shafts about 1150m long. The ore was carried down to Berth-Lwyd along two inclines.

John Latham, RCAHMW, 30 March 2012.
(Mining on the Dolmelynllyn Estate, Peter Crew & John Latham, 1984)