Gerry McDonnell
Archaeometallurgy
The key fundamental principal of the ‘bloomery process’ is that it was a solid state process. This principal underlies all the interpretations of iron artefact manufacture, including smelting and smithing technology, including slag chemistry ‘bloom-smithing’, slag inclusions in metal and the metal microstructure. The accepted model argues that the bloomery process was the method of iron production from the Iron Age through to the emergence of the blast furnace, which in Britain the accepted date is c.1496 in the Weald. However there is mounting evidence that this model is wrong. The evidence from the 13thC AD furnaces in Bilsdale North Yorkshire clearly demonstrate that they operated at very high temperatures which must have resulted in the production of cast iron. Secondly the evidence from the analysis of Saxon iron argues for molten metal production.
Pleiner (2000, *** argued for two tribes, those that believed in some role for liquid metal, and those firmly in the bloomery camp. I now belong to the former. The melting point of the smelting slags alone indicate that furnace operated at temperatures higher than previously thought