It was at one time proposed to treat the concentrated black iron obtained in the Ural gold washings, which consists chiefly of magnetite, as an iron ore, by smelting it with charcoal for auriferous pigiron, the latter metal possessing the property of dissolving gold in considerable quantity.
The great South Wales coalfield, one of the largest in the kingdom, covers the greater part of Monmouthshire and Glamorganshire, the south-eastern corner of Carmarthenshire, and a small portion of south Pembrokeshire, and the quality of its coal is especially suitable for smelting purposes and for use in steamships.
Shaft furnace smelting is confined to those parts of the world where charcoal can still be obtained in large quantities at moderate prices.
In unlimited supply, important deposits of rich iron ores suitable for smelting purposes; and for the manufacture of steel of certain descriptions abundance of manganese, chrome and tungsten ores are available.
A smelting plant was erected in the vicinity of Cerro de Pasco designed to treat moo tons of ore daily, a railway was built to Oroya to connect with the state line terminating at that point, and a branch line 62 m.
Lyell smelting works in Tasmania, which are of special interest, will be referred to later.
In the Carboniferous Limestone series, the purer kinds of limestone are used for the manufacture of lime, bleaching powder and similar products, also as a flux in the smelting of iron; some of the less pure varieties are used in making cement.
In the neighbourhood are mines of argentiferous copper, and the surrounding district and villages are occupied with smelting and similar works.
There are smelting furnaces in several districts, as at Alfreton, Chesterfield, Derby, Ilkeston.
In Mexico, Colombia and Peru the cutting of friable stone with tough volcanic hammers and chisels, as well as rude metallurgy, obtained, but the evidences of smelting are not convincing.