On Sat, 03 Jul 2004 00:38:46 GMT, Martyn Harrison
originally top-posted but I have
corrected this:


Apparently on date Sat, 03 Jul 2004 10:44:05 +1200, Eric Stevens
said:

On Fri, 02 Jul 2004 06:02:01 GMT, Seppo Renfors
wrote:



Gary Coffman wrote:

On Thu, 01 Jul 2004 08:26:52 GMT, Seppo Renfors wrote:
Gary Coffman wrote:
On Tue, 29 Jun 2004 05:48:01 GMT, Seppo Renfors wrote:
Gary Coffman wrote:
[..]
Again, porosity is the problem, and that should show up on
radiographs, as it does for R666 (which certainly shows evidence
of being melted in atmosphere, though not necessarily evidence
of being cast), but none of the other artifacts presented show
that sort of porosity.

See:
http://www.iwaynet.net/~wdc/copper.htm

The 4th and 5th pictures down.

Those pictures do not show any evidence of the characteristic
porosity copper casting would produce.

They disagree with you as it states "The casting bubble can clearly
been seen...."

And as I note below, they are quite wrong. It is rather obvious that
they have little practical experience or knowledge about working
native copper. It behaves significantly differently from other metals
when melted or cast.

Copper is copper no matter what part of the world it is in. ALLOYS
vary from place to place. So I find it hard to accept Michigan "native
copper" is much different from that here in Australia.

Michigan native copper is 'meteoric' copper. Australia does have some
meteoric copper (see
http://www.econs.ecel.uwa.edu.au/AMH...ett/news21.htm) but it is
accessible in quantitities very much smaller than in NA.


I would also direct your attention to this:
http://people.uncw.edu/simmonss/P6030052.JPG

There is little question this has been melted - and where are the
obvious faults?

Your authorities are a dentist, an engineer whose expertise is with
iron and steel, and one chemist (who disagrees with 4 others at his
school). Frankly, not a very impressive collection of authorities on
the metallurgy of native copper.

If you go to purchase a bottle of wine, which is the most important -
the label on the bottle or the taste of the content? The above is
pointing to the label, ignoring the content.

The single large surface
bubble is a blister, common when the surface of a wrought piece
is overheated. Compare it to the radiograph of R666. The latter
does show the characteristic deep pattern of porosity of an at least
partially melted copper object.

[..]


I'm fascinated by the "meteoric copper" idea.

'meteoric copper' is copper precipitated by the action of 'meteoric
water'. See http://www.webref.org/geology/m/meteoric_water.htm and
http://www.ocf.berkeley.edu/~tarcuri/finalproposal.html

"After hydrofracturing, temperature gradients and increased
permeability along fractures caused meteoric waters to circulate
through the pluton, effectively leaching metals from the porphyry
and precipitating them in hypogene, hydrothermal veins."

Apart from that, your interpretation of the term 'meteoric' as
referring to wacking great lumps of copper from space is
understandable but incorrect.


I'm ok with the notion that elements up to Iron are formed by gradual fusion
processes inside stars.

But as far as I know, that's where these fusion processes stop.

Copper isn't formed in that way.

So I can't see how a lump of space debris could reasonably be copper. It could
reasonably include a *bit* of copper, but not easily *be* a copper lump. Iron
yes, you certainly get lumps of iron when, e.g. a supernova goes whomp, but
copper, no I don't see how that's going to happen.

So I find it enormously unlikely that a lump made predominantly of copper might
end up as a meteor. Does anyone know if there is any credibility in this claim
in practice?


I hope not.



Eric Stevens