Tāngdān

Tangdan lies in the mountains of Dongchuan, a district famed for its copper. Its mines were worked under the Ming and became one of the great sources of copper for the Qing empire. Ore taken from the hills was smelted for transport, and copper from Dongchuan supplied the mints that cast the coins used across China. The Qing appointed officials to oversee the Tangdan works in 1705. Mining expanded greatly under the Qianlong Emperor, drawing labour and capital to the remote hills. The local gazetteer counted Tangdan among Dongchuan's most productive works, while officials concerned with the currency came to depend heavily on the province's copper.