I'm finding this discussion of the origins of metals very interesting - I
never gave it much thought.
How about mercury? It was used for gilding - when was it "discovered"?
Does mercury occur in its usual shiny liquid state naturally? How does one
"mine" mercury? (especially if it's oozing away from you as you dig a hole
in the ground or whatever)
Steve
> 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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