The spelter used must therefore be of a good grade, and the lead is usually first refined in a reverberatory furnace (the softening furnace).
Moreover, zinc and bismuth were confused, and the word spiauter (the modern spelter) was indiscriminately given to both these metals.
Commercial "spelter" always breaks under the hammer; but at Poo° to 150° C. it is susceptible of being rolled out into even a very thin sheet.
Spelter production began in the United States in 1858 in an experimental way, and regular production in 1860.
Among the manufactures are zinc spelter-there are large smelters here-clay products (chiefly vitrified brick, sewer pipe and tile; the clay being obtained from a great underlying bed of shale), blasting powder, packinghouse products and planing-mill products.
The town (which is often called "the metallurgical capital of Wales") is the chief seat of the copper, spelter, tin-plate and patent fuel industries, and has within a compass of 4 m.
Gold, silver, lead, sulphate of copper, spelter, tinplates, steel and iron, nickel and cobalt, yellow metal, sulphuric acid, hydrochloric acid, creosote, alkali, galvanized sheets, patent fuel as well as engineering works, iron foundries, large flour and provender mills, fuse works and brick works.
Copper smelting, which during most of the 19th century was the chief industry, has not maintained its relative importance, though Swansea is still the chief seat of the trade, but three-fourths of the tinplates manufactured in Great Britain and nineteen-twentieths of the spelter or zinc are made in the Swansea district, and its tube works are also the largest in the kingdom.
The Broken Hill Proprietary Company owns the principal mine, and at Port Pixie in the neighbouring colony of South Australia erected a complete smelting plant; the problem of the recovery of the zinc contents of the ore having been satisfactorily solved, the company made extensive additions to the plant already erected, and in 1906 the manufacture of spelter was undertaken.
From 1876 to 1897 the total value of the output of the Galena field was between $25,000,000 and $26,000,000; but at present Kansas is far more important as a smelter than as a miner of zinc and lead, and in 1906 58% of all spelter produced in the United States came from smelters in Kansas.