Tin mining in Cornwall
The St Just area in Penwith was an important centre for mining tin, copper and other minerals.
The earliest form of tin extraction was by 'streaming' of mineral-rich alluvial gravels. This involved the separation in water sluices of tin gravels from lighter material.
The resulting cassiterite (tin ore) was then smelted in furnaces (blowing houses) to produce molten tin metal. This was then poured into stone moulds to form rough ingots for transportation.
Digging into the ground
Most alluvial deposits became exhausted by the 17th century and other methods of extraction developed. These included the digging of shallow shafts and the excavation of tunnels or 'adits' into cliff faces or hill slopes along the line of the mineral veins. Later, a stamping mill pulverised the ore before separation.
During the 18th and 19th centuries, steam engines enabled deep-shaft mining and the draining and pumping of water from below ground. These advances produced the mining booms, which had such a lasting effect on the character of the Cornish people and the landscape.
Industry in decline
From around the 1860s, the mining industry declined due to foreign competition and many Cornish miners went abroad to find their fortune. It was said that 'wherever there's a hole in the ground, you'll find a Cornishman'.
There were sporadic, but weak recoveries during the 20th century until the closure in 1990 of Geevor mine at Pendeen brought a sad end to hard rock mining in the far West. The Geevor Tin Mine is now a heritage centre.