The Industrial Revolution brought about a tremendous change in the production of copper and its alloys. In the first place, an insistent demand arose for more and better raw material. In 1586 Ulrich Fosse, a German who was working the Cumberland copper mines, boasted that he could smelt 560 tons of copper ore in forty weeks. The 17th and 18th Centuries saw a vast improvement in this rate of output, largely arising from a quicker removal of impurities from the ore. By 1717 the Landore Works at Swansea comprised three large buildings, one of which was devoted solely to calcining. There were also thirty smelting furnaces for copper, lead and silver, a refining house, a test house and other outbuildings. (20)
In 1794 the Mines Royal at Neath Abbey were smelting 230 tons of copper ore per week to give 18 tons of copper. They used thirty-eight furnaces which consumed 315 tons of coal in the operation. The presence of good coal, in fact, was one of the reasons why the Swansea district became the centre of this industry; charcoal had been used right down to 1688 although as early as 1632 Edward Jorden discovered a new method of smelting by using pit coal, peat and turf as a fuel, and four years later Sir Philip Vernatt was granted a patent for the use of coal alone for that purpose.
Swansea was also an excellent seaport and was accessible to ships from all parts of the world which could bring ore from mines abroad.
During the 18th Century production in the nearby Cornish mines increased and a high output was sustained due to the introduction of steam pumps to remove the water from the diggings. This was the first use of steam power in mining and arose from the inventive mind of Thomas Newcomen, a Dartmouth blacksmith. Thus the Swansea district with its coal and commanding position became the greatest centre in the world of copper smelting and refining, a distinction which it retained until the latter part of the 19th Century. But a terrible price was paid; the local atmosphere in what had formerly been the beautiful green valleys became so foul with sulphurous fumes that it was said that if the Devil were to pass that way he would think he was going home. (21)
The cost of copper, in those days, was very great. In 1714 cake copper, unrefined, fetched £100 per ton, and plates as they came from the battery works cost £140 to £150 per ton. In 1694 Swedish copper, which was then regarded as high quality, cost £168 per ton. These figures, currency for currency, far exceed modern prices. On the other hand, the entire English output of English copper at that date was only about 100 tons per annum.
21 Ibid. p. 408.