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Seppo Renfors
 
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Default Copper Casting In America (Trevelyan)



Gary Coffman wrote:

On Thu, 10 Jun 2004 15:36:41 -0400, Yuri Kuchinsky wrote:
Copper Casting In America (Trevelyan)


[..]

So here we see the sort of an anti-Native bigotry that is
still all too common within our professional archaeological
establishment. These folks really still live in the middle
ages!

What a dark snake-pit of racism and bigotry our academic
establishment is... This never ceases to amaze me, I must
say.

This is the Dumbing-Down Crew that is hard at work to deny
the cultural achievements of Native Americans.


Realize that casting is primarily a technique used for cheap mass
produced items. It allows relatively low skilled workers to produce
large numbers of relatively complex identical items. Cold working is
a much more challenging, and artistically unique, way to produce
intricate copper ceremonial items. The smith has to have a higher
level of skill than the foundryman to produce equally complex work.

Given that, it seems to me that your claims of bigotry by a art
historian are unfounded. If anything, the idea that the art objects
were produced by cold work makes them even more impressive
examples of the skill of the worker than if they were mere castings.


Whilst there is little argument with that, it is still illogical to
believe that casting wasn't done. Each maker of jewellery, ceremonial
items would have ended up with "scraps" of copper. It is unlikely they
would have simply been thrown away. The annealing of copper would
bring it to melting temperature often enough for smaller thinner bits.
It suggests a very likely occurrence that they did melt copper, if for
no other reason than to make bigger pieces out of the small scraps and
off-cuts. This they would again cold work another time.

But that said, casting pure copper is a bitch. Porosity is the enemy,
even for modern copper founders. They charge a hefty premium for
low porosity castings. Alloying the copper to make bronze improves
matters *enormously*, and production of such alloys was a huge
technological leap forward for the casting industry.

*If* the Native Americans of millenia past made the technological
leap of producing bronze alloy, it would be a significant achievement
(as it was when Old World artisans did it). But I've seen no evidence
produced in this thread that the ancient Native Americans made
such a technological leap forward.


IIRC silver is found in with copper deposits in the Great Lakes area
and it has a melting point a bit lower lower than copper. It is likely
they could have used a silver/copper alloy or "bronze". If the
minerals co-exist then there is no need for "mixing", it is automatic
as with arsenic/copper deposits.

The artifacts described appear to all be relatively pure native copper.
As such, the *intelligent* way of working the material would have
been smithing rather than casting. So if the motive were to make
ancient Native Americans appear stupid, then claiming that they
used open casting techniques would be the method of choice to do
so. Now ask yourself which side of the argument is making that
claim.


You see, the thing is that cold working something doesn't require
"technology", where melting/smelting does. It is the implied lack of
technology where the suggested prejudices arise from.

--
SIR - Philosopher unauthorised
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The one who is educated from the wrong books is not educated, he is
misled.
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