During the mining boom, Hayle had two of the three largest mine engine foundries in the world (Harvey's 1779-1903 and Copperhouse 1820-1869). Copperhouse Foundry traded as Sandys, Carne and Vivian.
Copperhouse was so named as it was the site of the copper smelters for the mines in the area. The Cornish Copper Company established this site in 1758. Copper ore from Cornwall then was then shipped to South Wales.
The first major development at Hayle was the construction of the quay by John 'Merchant' Curnow in the 1740's to service the mining industry. In 1758 the Cornish Copper Company moved from Camborne and set up a copper smelter at Ventonleague (Copperhouse Creek) and a canal was dug to bring vessels right up to the works.
The smelting process generated large amounts of waste. The copper slag was cast into large heavy dark bricks called locally 'Scoria Blocks' which were used as a building material in the town and can be seen today in many buildings. The blocks were sold at 9d (about 3p) for 20 and given free to employees of the CCCo to build their own houses.
Copperhouse Pool was later modified to serve as a tidal reservoir to allow ships to travel up as far as the dock, and to flush or sluice the channel to keep it clear of sand and silt.
In 1779 John Harvey, a blacksmith from nearby Carnhell Green established a small foundry and engineering works. The business flourished and by 1800 employed more than 50 people. The firm continued to grow, and produced some of the finest beam engines ever built. They were used both in Cornish Mines and were exported worldwide.
As Harvey's and the Cornish Copper Company developed a rivalry which grew into open hostility. Disputes erupted over access to the sea as The Cornish Copper Company controlled the dock and the tidal sluice.
Harveys eventually broke the Cornish Copper Company's monopoly by constructing their own harbour by deepening Penpol Creek and building a dock. They even constructed their own tidal reservoir and sluice by creating Carnsew Pool.
Harvey's their rival, produced some of the largest steam engines ever built anywhere. Harvey's took over the Cornish Copper Company in 1875. And as the mining boom folded in Cornwall, the engineering works and Foundry were closed in 1903 though the company continued to trade as general and builders merchant, eventually merging with UBM to become Harvey-UBM in 1969. Despite the demolition of much of Copperhouse Foundry and of Harvey's, much of the historic industrial town and port of Hayle is still largely intact. The Kew Bridge Steam Museum has a 90" engine, largest working beam engine in the world. It was built in 1846 by Sandys, Carne & Vivian of Copperhouse Foundry, Hayle, Cornwall and was the first engine built in Cornwall specially for waterworks duty.