United Mines is the union of Ale and Cakes Mine, Wheal Cupboard and Poldory who amalgamated in about 1780. These mines are just to the south of the Great Consolidated Mines in the parish of Gwennap and border the villages of St. Day and Crofthandy in the west and the Poldice and Carnon valleys in the north. Some time later the group was expanded to take in the mines of Wheal Britannia, Wheal Clifford, Wheal Moor, Wheal Squire Wheals Squire, Wheal Andrew or Friendship Mines, and Copper Hill Mine.
Little is known of the history of the individual mines of the United Mines group. Poldory was probably active in 1760. It appears to have commenced production as a small scale tin mine and then been combined with other small-scale mines in the area in 1815 under the name of United Mines.
In the early 1820's John Taylor acquired the lease of abandoned mines in Gwennap parish and initially re-worked their setts before striking the richest copper lode in the world (at that time). The Gwennap Mines were well in profit by 1822.
The chief production of the area was copper at that time, although there was some tin and ochre mined. The output was then shipped north to the port of Portreath for smelting in south Wales, along the Portreath Tramroad. However as the mines became more profitable, the tramroad owners put up the price for trans-shipping. John Taylor countered by constructing his own tramway south through the Carnon Valley to Devoran on the south coast. Initially horse-drawn the Redruth and Chasewater mineral tramway opened in 1824, and was converted to steam in the middle of the nineteenth century. The railway operated for over 90 years before finally closing in 1915.
Eldon's pumping engine house, also known as Little's, operated a 30-inch cylinder pumping engine and was built around the 1830's. It was mainly used was for pumping water from the adit to the surface.
United Mines continued to expand, and eventually amalgamated with the neighbouring Consolidated Mines in 1857 to form 'Clifford Amalgamated Mines'. At its peak the mines here had 80 miles of underground workings, and 22 engines. In 1861 the whole group was included with Great Consolidated as Clifford Amalgamated Mines. Wheal Clifford produced 50,167 tons of 6.5% copper ore and 365 tons of black tin during the years 1835-61. The other mines of the United Downs group produced 347,500 tons of 7.5% copper ore, 250 tons of black tin, 158 tons of arsenic, 1,290 tons of pyrite and 271 tons of zinc ore during the years 1815-61.
Falling metal prices finally closed the mines in about 1870.
"The chief lodes (Hot Lode and South Lode) intersect Elvan dykes striking
approximately E-W and dipping 30° north. Hot Lode and South Lode strike
E-W and dip 20° N and have been exploited throughout the history of the
mine. Several lodes have been mined for shorter periods, mainly branches or
droppers from other lodes. Hot Lode ranges from 15-185 cm in width and consists
mainly of fluccan, quartz and copper ores. Great South Lode outcrops 155 m south
of Hot Lode and consists of quartz
with chalcopyrite and pyrite at deep levels barite forms a lining to vughs. Many of the smaller veins consist of tourminalized strings through quartzose schists forming disseminated deposits of barite and chalcopyrite (Dines, 1956)."
The area was prospected again in the 1940’s and brief trial mining operations were conducted but no commercial mining took place.
Gwennap Area Mines.