James,
High carbon alloys are not uncommon amongst the debris from bloomery smelting
sites. They are often ignored as they look like rusty slag. I have found cast
iron from Carhampton, Somerset - a 5-7th century AD bloomery/bloom refining
site, where the material recovered from normal low carbon material through
to prill and small lumps of grey cast iron; at Brettenham in Norfolk, I found
material varying from ultra high carbon steel to low carbon cast-iron in the
debris from the periphery of a smelting site (the site itself was not located).
I have examined other high carbon raw bloomery steels from
Nicopolis, Romania (upto 1.7 %), and an Irish Iron Age site I am currently
working on appears to have a variety of carbon contents including
hyper-eutectoid material. That is all raw material, but Roman billet found in
2nd-3rd century smith's workshop from Carmarthen was 1.4-1.7 % carbon, shows
that at least some of this material was selceted and used (the billet had a
corner cut off).
Unfortunately, I can not give you references for this as all this material is
either in preparation for publication or in press.
Chris Salter
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