>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
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