If you have access to zinc bearing minerals you don't need to make Zn to make zinc brass, and Bulgaria and Sardinia both have, even now, deposits of the Cu-Zn minerals rosasite and aurichalcite. I think it quite reasonable that in Hellenic times brass was being deliberately made at the fringes of the civilised world and sold to Greeks, no one understanding why addition of the Cu-Zn minerals to the production process produced this material, though the makers must have understood that it was copper plus something that wasn't tin.
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There is some confusion here between the deliberate and the accidental
making of zinc metal. There was also a failure to recognise the product as a
different metal. There could only be seven metals and they had found them
all.
Conditions in a lead smelting furnace are ideal for reducing zinc, but it
is, of course, a vapour not a liquid. Usually the vapour re-oxidised in the
chimney and was collected as fairly pure zinc oxide. It was used for various
purposes, including medicine.. Ocasionally there were nooks and crannies in
the chimney where conditions were right for the zinc to condense. It was
found when the furnace calamine was collected, was a curiousity, and usually
was thought to be "false silver". It was cast into trinkets. Bracelets were
found in the ruins of Cameros (before 500BC). Most of these
will have corroded away. I cannot offer a reference to early Egypt but once
lead smelting furnaces with chimneys were in use it seems likely that there
would be occasional finds of this false silver. Paul Craddock will probably
know.
Brass seems to have been invented at around the beginning of the Christian
era and was spread around by the Romans. Again alloys containing zinc have
been found in antiquity, almost certainly made accidentally.
The deliberate production of zinc in India and China seems to have begun in
the 14th century or earlier- there are Chinese coins from 1402 which
suggests that an appreciable quantity was available. It was imported into
Europe in the 16th century under various names.
Peter Hutchison
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