Yes, one or two pictures would be good for comparison, Eugster and
Wones (1962)is the referecne which Hauptmann et al (2002) use for this
thermodynamic argument, and if you have even got cuprite in copper (in
the copper itself or only in the slag phase?) then where does that
leave the argument for the lack of cuprite in directly smelted copper?
Quoting Aaron Shugar <[log in to unmask]>:
> David,
>
> I have seen extensive cuprite growth in fayalitic smelting slag from the
> Chalcolithic Near East. Of course this is fairly basic copper smelting with
> limited superstructure furnaces so they were not very efficient, but I can
> send you a few pictures if you like.
>
> Aaron
>
>
>
> On 3/5/07, David Scott <[log in to unmask]> wrote:
>>
>>> Hallo All....I wanted to ask your opinion on the issue of cuprite
>>> inclusions in smelted copper....according to Hauptmann et al writing
>> about
>>> the copper oxhide ingots and tin ingots from the Uluburun (Sp?) shipwreck
>>> site they say, [contra Tylecote 1976] that we cannot have primary cuprite
>>> from the smelting of copper ores because the equilibrium conditions for
>>> the formation of a fayalite slag preclude the Cu/Cuprite eutectic being
>>> possible and that only in melting would one find that cuprite is present.
>>> In other words we can have primary cuprite, but only from melting of
>>> previously extracted copper, not from the smelting stage per se. But on
>>> examination of some experimental copper smelting from malachite at about
>>> 800 degrees C which would be pertinent for the Late or Final Neolithic of
>>> European copper smelting which I made several years ago, I find "primary"
>>> cuprite inclusions within the copper prills which were produced during
>>> this experiment. If these prills were then subsequently melted in a
>>> crucible, the copper may well pick up more oxygen, but we would still
>> have
>>> cuprite inclusions from the original smelt present. Now, the smelting
>>> conditions are not in equilibrium with a fayalitic slag of course at all,
>>> so does this invalidate the argument by Hauptmann et al and suggest that
>>> Tylecote was not entirely wrong? Can one always assume that the
>>> production of ox-hide (or other ingots) would have had to rely on smelted
>>> copper produced with the kind of slag associated with more "advanced"
>>> copper extraction processes rather than the remelting of small copper
>>> prills? Best wishes to all.....Professor David A. Scott.
>>
>>
>> Professor David A. Scott
>> Chair, UCLA/Getty Conservation Program
>> The Cotsen Institute of Archaeology, Room A410
>> University of California, Los Angeles
>> 405 Hilgard Avenue
>> Los Angeles, CA 90095
>>
>
>
>
> --
> Aaron Shugar
> [log in to unmask]
> [log in to unmask]
> [log in to unmask]
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