From Graces Guide
Consolidated Mines are in the parish of Gwennap, union of Redruth, hundred of Kerrier, Cornwall, within the bounds of the manor of Cusgarne, and mining district of Gwennap; it is situated 3 miles from the town of Redruth.
The Consolidated Mines (colloquially known as Consols) were formed in 1780 and comprised the eighteenth century mines of Wheal Virgin, West Wheal Virgin, Wheal Girl, Wheal Maid, Wheal Fortune and Carharrack Mine.
The seven Newcomen engines were replaced by five Boulton and Watt engines, later increased to seven. Like United, between 1792-98 Consols realised a profit of over £200,000 on a capital of less than £20,000. The falling price of copper on the world market combined with the rising cost of running the Newcomen engines conspired to close both mines in around 1805.
In 1811 United was restarted by Joseph Sowell of Penryn, who on account of his trickery with floating the shares, was soon dismissed and the Williams' of Scorrier took over the running of the enterprise.
By 1814 the company had been equipped with 63" cylinder pumping engines. The mine sett at this time was something over a mile and a half in length.
In 1819 United and Consols mines were taken over by John Taylor (1779-1863) and sons who turned these mines into the largest copper producer in the world. Two 90" engines were erected on Fortune's and Job's Shafts. By 1820 they were producing a larger quantity of ore than any other group in Cornwall, a position they retained for the next 20 years.
In 1824 United Mines were joined to those of Consolidated, although each continued to keep separate accounts.
By 1838 the combined group was being operated by 10 pumping engines, three of which were 90" cylinder, whilst there were 11 other steam engines for winding and crushing. The mine employed a total of 3,196 men, women and children.
On an initial expenditure of £65,000, between 1819-40 Consolidated yielded to the shareholders £480,156 in dividends. In the first 18 years of this undertaking the underground workings amounted to a total of nearly 63 miles.
In 1840 the Taylors' lease expired and "not being able to agree with the owners for a renewal they picked the eyes out of the mine", which then passed back to the Williams. Between 1840-42, 25,407 tons of ore was sold for over £160,000 and yielded an amount in excess of £16,000
Working conditions were gruelling. Temperatures at the 300 fathom level in Consolidated were 96 degrees fahrenheit, exceeded by those in United at 100 degrees with water issuing from the ground being 96 degrees. In 1845 a man engine was installed as it took over an hour and a quarter to ascend the mine after working in appalling conditions.
By the mid 1840s the mine was a shadow of its former self and by 1850 copper production was down to just 6,000 tons and it closed in 1858. The deepest workings from surface were then 320 fathoms, 2,000 people relied on the mine for employment, and the machinery had an estimated value of £70,000.
1861 the whole group was worked as Clifford Amalgamated Mines which itself was stopped in 1870.
Sources of Information
-  Cornish Mining