Excavations are reported on one of the last generation of charcoal blast furnaces built in Britain, and the best preserved in Wales. There were iron slags, floor or yard surfaces, and a wheelpit of the silver-refining phase. The blast furnace, ca. 1755, was freestanding, with a cast house, charging bridge, etc., added later. The final blowing was ca. 1810, after which came a sawmill and a 9 m waterwheel.