Copper was at first obtained in this country in small quantities in working the tin mines in Cornwall; but about the close of the 17th century mines were set at work purposely for copper. Improvements in the art of smelting have greatly increased the products of the mines, and ores which produce only three or four per cent. of metal are now smelted. The average annual produce of the Cornish mines was only about 3,300 tons in 1780 ; the later produce we shall presently have to mention. The value of the produce of all the British copper-mines is in good years about 1,500,0001. Four-fifths of the whole quantity is raised from the Cornish mines ; the rest being de rived from Devonshire, Staffordshire, Angle sey, and the Isle of Man.
The duty on foreign copper ore, previous to 1842, was 121. a ton, and on smelted but unwrought copper 271. a ton ; these rates were greatly lowered in 1842, and were reduced to merely nominal amounts in 1848.
The Cornish copper-ore sent to Swansea to be smelted, from 1820 to 1850, has varied from 100,000 to 160,000 tons annually. The
quantity has gradually increased, but the quality of the ore has deteriorated. The selling value of this ore for the last few years has been from 800,0001. to 900,0001. Between 1844 and 1818 the foreign copper ore smelted at Swansea varied from 96,0o0 to 47,000 tons annually. The whole of the ore,British and Fo reign, smelted at Swansea during the sixteen years from 1833 to 1848, has yielded the fol lowing averages: Average quantity smelted .. 194,142 tons.
Average piice per ton .. £7 7s.
Average money value .. £1,424,818 Average produce of copper .. 18,567 tons.
Average richness of ore .. 101 per cent. In 1848 four firms at Swansea purchased and smelted no less than four-fifths of all the British and foreign ore smelted in Great Bri tain ; the firms were those of Messrs. Williams and Foster, Messrs. Vivian, Messrs. Simms and Willyams, and Messrs. Grenfell ; and the value of the ore purchased by them exceeded 1,100,000/.