Devon Great Consols, Tavistock District, includes the mines of Wheal Maria, Wheal Fanny, Wheal Anna Maria, Wheal Josiah, Wheal Emma, which lie from west to east along the main lode and were the main sources of copper then arsenic in the later days as copper ran out. Wheal Frementor, Watson's Mine and Bedford United Mine all lie south of the main lode, Frementor (also called Framator) was mined latterly for tin in the most part and did not finally close until 1930.
At its peak in the later part of the 19th century Devon Great Consols was both the largest copper and arsenic producer in the world and was at the cutting edge of ore recovery technology under the control of Captain Issac Richards. The mine ceased production in 1901 and was abandoned in 1903. Throughout the twentieth century the mine was worked on a much smaller scale for a number of minerals including copper, arsenic, tin and wolfram.
1844, the greatest copper lode in Europe was discovered near Morwellham. A new company which became known as Devon Great Consols was formed to mine the ore. The mine was only 4 miles from Morwellham Quay, but it lay in a different direction from the canal and could not use it for tranport. Despite earlier attemps the mine did not become a going concern until Josiah Hitchins took up a lease in 1844. The lode was struck just 4 fathoms below the bottom of the previous working in Gard's Shaft at the western end of the sett. Within 6 months and at only 28 fathoms in depth this shaft was 'cutting yellow ore from corner to corner' and in March alone 810 tons of ore was sold.
1845 a total £72,704 profit was divided.
1845 Wheal Fanny was started and the lode was cut only 3 fathoms below the surface.
1855 Mar 24 William Morris (he of wallpaper fame) came of age and received his inheritance: 13 shares of Devon Great Consols. The dividends provided him with income of over £700 a year. Morris was a shareholder and sometime director Devon Great Consols. Morris was well aware that many of his workers suffered arsenic-related illnesses, working conditions were atrocious. Morris, however, chose to dismiss the contemporary health concerns over the pigment arsenic green and ignored the massive environmental damage his mines caused. However Morris eventually resigned his inherited directorship of Devon Great Consols, and sold his shares, in 1876, (he said "My relations thought me both wicked and mad") just when his firm's wallpaper production really began to take off.
1856, the mine owners constructed a railway to the hill above the quay and a second inclined plane railway was built, passing through a tunnel beneath cottages and the village green. Extensive quays and a massive new dock were built. Morwellham Quay had yet again doubled in size and was hailed as ‘the greatest copper port in Queen Victoria’s empire.’ 300 people lived there and ships from all over the world brought the vital supplies needed to work the mines and took away the cargoes of ore.
1856 In March with the lode being worked on its full length from Wheal Maria to Wheal Emma 3389 tons of ore were sampled, an all time record for Cornwall. The 1856 year total was 28,836 tons. The only limiting factor on output was transport and storage to the quays at Morwellham.
1860 the lode at Anna Maria was up to 45 feet wide and yielding up to 80 tons per fathom.
1870 refined arsenic was also being produced from arsenopyrite deposits up to 6 feet thick which lined the copper lode and had previously been left in place as having no value. The mine produced over half the British output and only limited output to avoid depressing the world market price.
1880 the copper boom was over. Arsenic production sustained the mine for another 20 years until the original compsny folded in 1901.
As copper began to run out, arsenic ore was mined instead. This provided the deadly poison which was used in insecticides and weed killers. It was once said that there was enough arsenic stored on the quayside at Morwellham to kill every man, woman and child in the world. When Devon Great Consols eventually closed thousands of miners were forced to emigrate in order to find work. The quays fell into disrepair, the docks silted up and the place became almost forgotten.
The overall output from 1844 to 1902 had been 736,229 tons copper ore sold for £3,473,046 and 72,279 tons refined arsenic for £625,062.
Tamar Valley Mining