The Duchy Tin & Wolfram Works were active from 1916 to 1921 and were on the Western slopes of Kit Hill. The East-West mineral lodes were exploited by openwork trenches in some cases leading into underground levels. The nearby carpark off the road (to the left) to Kit Hill summit part way up is built on the dumps of the mine.
In the latter part of its operation, ore was lowered down a short steep inclined tramway then taken by carts to another short level tramway (the embankment can be clearly seen) leading to the loading point of an aerial ropeway. The ropeway went to the Clitters Utd mill and was 2.5 miles long and could carry 20 tons per hour in skips. It was operated by 4 men and 4 boys. The concrete remains of the loading point survive relatively intact at SX385712