Dyffryn Adda Copper Furnace and Precipitation Ponds

Cadw's description

Summary description and reason for designation

The following provides a general description of the Scheduled Monument.

The monument consists of the remains of a reverberatory furnace and precipitation pits dating to the 19th century. The Mynydd Parys Copper Mines were by the eighteenth century the most productive in Europe, extracting ore by opencasting, underground working and precipitation. Dyffryn Adda furnace is the only identified reverberatory furnace for copper smelting surviving in Wales, which was the most important region in the world for copper production. Such furnaces were once common features in the copper processing industry of Wales. The associated precipitation ponds are the best surviving example of a method of extraction practised extensively on Mynydd Parys but nowhere else in Britain. They are believed to have been used from c.1818 to c.1958. Other features include buildings associated with the reverberatory furnace, including a derelict cottage and the entrance to the Dyffryn Adda adit from which the precipitate was derived.

The monument is of national importance as a unique survivor of reverberatory furnace technology in association with an important adit and precipitation ponds and for its potential to enhance our knowledge of industrial mining practices. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.