Part of St. Ives Consolidated. The Trenwith mine, initially known for its copper and tin ores, gained prominence as a uranium producer in later years. Despite producing significant amounts of copper and tin between 1825 and 1856, totaling 13,080 tons of copper ore and 20 tons of black tin, it became recognized for its uranium content. Pitch-blende, mistaken for black copper ore, was found abundantly among the copper ores. Its true nature was discovered by Mr. Michell of Calenick, leading to the rejection of pitch-blende due to its detrimental effects on copper smelting.

After a period of dormancy lasting over 50 years, the mine’s dumps were reworked for uranium ores in 1907. A newspaper report from that time highlighted the richness of the pitchblende in the mine’s dumps, sparking renewed interest in its exploitation. In 1908, Wheal Trenwith, along with neighboring mines, was acquired by St. Ives Consolidated Mines Ltd., which resumed reworking the mine’s dumps and levels selectively above 60 fathoms. Between 1911 and 1917, the mine produced 694 tons of uranium ore, primarily from dump material, with some underground patches found in thin films in joints.

Following the acquisition of St. Ives Consolidated Mines by the Thermo Electric Corporation in 1917, operations at the northern mines were ceased, and focus shifted to Giew Mine. Much of the Trenwith mine site is now occupied by a car park.

1905-1908 1917-1920