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Seppo Renfors
 
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Default Copper Casting In America (Trevelyan)



Gary Coffman wrote:

On Wed, 30 Jun 2004 14:53:00 -0400, Yuri Kuchinsky wrote:
Gary Coffman wrote:

[snip]

The apparent fact that the Native Americans *didn't* cast native
copper


This is a "fact" only if you disregard all evidence to the
contrary, as you appear to be doing.


Virtually all of the evidence presented to date in this thread is
against casting of ancient Michigan native copper artifacts. If
you have conclusive evidence showing characteristic porosity
in all the items claimed to be cast, if you have evidence showing
a chemical analysis of true alloying between the native copper
and other metals (mainly silver) found with it in the halfbreed
ore matrix, if you have evidence of large numbers of identically
dimensioned artifacts representative of a casting provenance,
etc, then present it. Otherwise you have no case.


You cannot claim "you have no case" UNLESS you prove there is no "true
alloying between the native copper and other metals" and that takes an
analysis of the metals in the artefacts found. It works both ways you
know.

What we do know is that ancient Michigan artifacts have been
found with silver inclusions. That precludes the possibility that
they were ever melted.


No, it precludes that item from having been melted only. You cannot
extrapolate that beyond the artefact itself.

We do know that of the artifacts which
have been put forward as evidence of copper casting, all but
one do *not* show the characteristic porosity of atmospheric
melting of copper, and that one does not appear to be a deliberate
casting.


We see TWO artefacts being claimed as being cast - one being conceded
as being cast. We don't know the composition of the metal of the
second artefact to be able to discard it as "not cast".

You have claimed it is the sign of "copper" being overheated - ie to
melting point else bubbles cannot form. At the same time you have also
stated the heat source has to be forced air type to get it hot enough
to melt copper.

I see those two statements as being inconsistent with each other. If
the Copper was simply hammered and annealed, the temp should NOT be
able to get high enough to cause any bubbling.

ON the other hand in the event the fire was of the type for melting
copper.... well.... then it would be for melting copper, why else
would it be like it?

We do know that there is no need to invoke casting as the
manufacturing method of any of the artifacts, ie it has been
demonstrated that any of them could have been smithed
from native copper without casting using tools and techniques
known to have been available to the Native Americans of
Northern Michigan. And we have the testimony of an experienced
coppersmith that casting would have been a greatly inferior
method of producing them.

The burden of proof is on you to present incontrovertible
evidence that any of the Michigan artifacts were in fact cast.
So far, you have not done so.


No, I don't see it like it at all. The alternative is to argue that;
without any research we can definitely say none were cast, barring one
exception. That of course is illogical as all hell. NO such thing can
be claimed at all.

--
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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