Copper ores had been known in Cornwall from an early date.
Attempts to work Cornish Copper ores for profit had started in the 16th century with imported German expertise. They failed and little was done for most of the 17th century. However, improved smelting techniques, largely connected with the introduction of the reverberatory furnace at the end of that century, finally began to make their exploitation viable and mining began to expand during the early 18th century.
Copper mining experienced steady growth from the beginning of the 18th century. From 1750 to 1850 copper was the most important mineral in the region.Cornwall's copper output dominated the world’s copper markets.
Technical advances in stream pumping shaped the beginning of the Industrial Revolution in Cornish mining. The creation of the industrial transport infrastructure during the late 18th century was essential to the production of copper.
In 1785 the exploitation of the large and shallow deposit of copper ores at Parys Mountain in North Wales caused a sharp economic decline in the fortunes of Cornish Mines. During this period, British copper production exceeded demand, and there were struggles for the control of the copper market between smelters and Cornish producers caused a surplus of copper on the world market. Triggering many mine closures. However, the copper ore in North Wales were worked out within 20years and during this time Cornish miners had made huge improvements in pumping technology and working methods. During the early years of the 19th century Cornwall had once again become the top copper ore producer in Britain, and the world. This remained so for several years.
In the 1830s Cornwall completely dominated world copper production. Gwennap Mines produced 442,493 tons of copper between 1819 and 1858 and the United Mines produced 347,640 tons from 1815-1861: this area was so rich in copper it was called the ‘Copper Kingdom’. However two decades later Chile’s production outdid Cornwall’s copper output. Cornwall and Devon’s peak year for copper production was 1855-1856, when 209,305 tons of ore were mined. By the end of that decade tin replaced copper as the regions most important mineral. In 1866 there was a crash in the copper market and Cornish copper mining could not survive.
Some Cornish mining districts were fortunate as they also possessed tin reserves, and they were able to continue to function as Tin mines.
Photograph reproduced with the kind permission of the Royal Institution of Cornwall