Alasdair:
 
You might also check out Henry Unglik's "Ironworking at an Early Nineteenth
Century Blacksmith Shop, Fort St. Joseph, Ontario: An Examination of Slag and
Iron" in: A Frontier Fur Trade Blacksmith Shop, 1796-1812 by John D. Light
and Henry Unglik, revised edition, Studies in Archaeology, Architecture and
History, National Historic Parks and Sites, Environment Canada - Parks,
Ottawa, 1987.
 
Unglik provides a chemical and microscopic analysis of slag material, pieces
of metal found in slag, iron objects, melting points of slag, formation of
slag material and ironworking at the blacksmith's shop.
 
Pat Tucker
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