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GoAntiques inventory consists of antique, collectible, art, and other merchandise for sale by member dealers. Along with TIAS.com, and Ruby Lane it was long ago considered one of the 3 major online antique malls. [2] As of July 2014, the site lists more than 400,000 items from 1,800 dealers in 29 countries.
In a smelting furnace, up to four different phases might co-exist. From the top of the furnace to the bottom, the phases are slag, matte, speiss, and liquid metal. [3] Slag can be classified as furnace slag, tapping slag or crucible slag depending on the mechanism of production. The slag has three functions.
The smelting and melting process also changed with both the heating technique and the crucible design. The crucible changed into rounded or pointed bottom vessels with a more conical shape; these were heated from below, unlike prehistoric types which were irregular in shape and were heated from above.
Iron alloys are most broadly divided by their carbon content: cast iron has 2–4% carbon impurities; wrought iron oxidizes away most of its carbon, to less than 0.1%. The much more valuable steel has a delicately intermediate carbon fraction, and its material properties range according to the carbon percentage: high carbon steel is stronger but more brittle than low carbon steel.
The metal would have been found in nature without the need for smelting, and shaped into the desired form using hot and cold hammering without chemical alteration or alloying. As of 1999, "no one has found evidence that points to the use of melting, smelting and casting in prehistoric eastern North America." [3] (p 136)
The problem of mass-producing cheap steel was solved in 1855 by Henry Bessemer, with the introduction of the Bessemer converter at his steelworks in Sheffield, England. (An early converter can still be seen at the city's Kelham Island Museum). In the Bessemer process, molten pig iron from the blast furnace was charged into a large crucible, and ...
16th century cupellation furnaces (per Agricola). Cupellation is a refining process in metallurgy in which ores or alloyed metals are treated under very high temperatures and subjected to controlled operations to separate noble metals, like gold and silver, from base metals, like lead, copper, zinc, arsenic, antimony, or bismuth, present in the ore.
Crucible Steel Company of America, Condensed suggestions for steel workers. BiblioBazaar (1902, reprint 2010) ISBN 9781175479105; Crucible Steel Company of America, High Speed Steel. (1912, reprint 2011) Nabu Press, ISBN 9781272198145; Crucible Steel Company of America, Crucible Steel Company of America (1925) ASIN B002683KAG