Responses to criticisms about Mack et al. 2000 posted on arch-metals:
(in no particular order).
1. "The claim of Mack et al. cannot be entertained until there is
evidence of (1) cast iron<HORIZONTAL ELLIPSIS>" Killick 04/01/01
The analysis of one stock iron artifact composed partially of white
cast iron is provided (p 94, Fig 11)
2. " I accept that the steel may have been molten, but this hardly
justifies the assumption that it must have been produced by the
decarburisation of cast iron." Killick 04/01/01
This was not the argument presented in the paper. The steel was
molten. All of the stock artefacts reported in the paper had features
which were interpreted as resulting from solidification. Where
artefacts were not in an as cast state ie, following subsequent forging
and heat treatments (such as in a blacksmiths chisel), etching with
reagents identified segregation of trace elements in a distorted
dendritic pattern.
There are several processes by which a liquid steel can be produced,
however most of these require crucibles. As none were found the likely
process cannot have been a crucible technology. As cast iron was found
on the site the authors explored the possibility of utilising a cast
iron feedstock for a liquid steelmaking process - a decarburisation
process.
3. "I am not totally convinced by this, as the same process can occur
naturally within the bloomery furnace, all that is required [is] a
bloom master with the skill required to control the bloomery
temperature, and then to separate out the different types of metal from
the bloom<HORIZONTAL ELLIPSIS>" Salter 03/01/01
"<HORIZONTAL ELLIPSIS>there are numerous instances of slag free steel from known bloomeries
- <HORIZONTAL ELLIPSIS>" Killick 04/01/01
The authors have also seen hyper-eutectoid steels, some as-cast, some
forged to bar, and cast irons at a British bloomery site of the same
period, and experimental bloomery smelting has demonstrated the ease
with which cast irons and steels can be produced in the bloomery
furnace. However, 8th-9th century Hamwic has produced little or no
evidence for smelting, in either archaeological features or in the slag
examined. The artefacts in question were recovered from
stratigraphically sealed deposits within a structure whose primary
function, as evidenced by archaeological features, slags and residues,
and tools, was secondary smithing. The composition of these artefacts
would have made them difficult if not impossible to forge without
secondary processing. If the authors are wrong in their conclusions
then the presence of this material in a smithy cannot be explained.
4. " I am afraid that this paper is symptomatic of a widespread
problem in British archaeometallurgy, which is its insularity<HORIZONTAL ELLIPSIS>"
Killick 04/01/01
Whilst the authors consulted papers concerning steelmaking from a range
of European and non-European perspectives, including both Killick's and
Juleff's work, it would seem only common sense to focus on the
metallurgical data from the artefacts themselves. The authors find it
hard to believe that the best method in which to understand steel
production in 8th-9th century Hampshire, is by consultation of 19th
-20th century African ethnography. In contrast with Taylor and Budd,
the authors were not using any large scale sociological theory but
essentially reporting on data generated from the analysis of early
medieval ironwork from Saxon Southampton. This data has provided
tentative evidence for a process by which high quality steels were
produced in antiquity, rather than alternative theories which rely on
assumption and inappropriate analogy. In this respect the authors
believe an insular approach has merits. Rather than forcing new data
into some overriding worldwide model of ironworking which ignores
regional differences in technology, the authors believe that
archaeometallurgical analysis is the primary means by which to
understand the processes utilised by early metal workers in any given
locality.
Finally, is the hypothesis that in Western Europe, (small?) quantities
of cast iron were deliberately produced and utilised prior to the
introduction of the blast furnace, such an unexpected and unpalatable
theory?
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Ivan J Mack
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