[meteorite-list] Re Cu meteorite

From: Pete Shugar <pshugar_at_meteoritecentral.com>
Date: Sat, 12 Jul 2008 00:16:48 -0500
Message-ID: <000201c8e43f$87321ca0$0201a8c0_at_portable>

Greeting list,
I am by no means an expert. From all that I've read from this fine list of
experts
and scientists, meteorites come in several packages, i.e., irons,
stony-irons and
stonys. (I'm keeping it simple.)
I haven't ever heard mentioned of a meteorite composed of copper.
Now, copper I know. This is because I've a degree in electronics.
Gold and silver make better conductors than copper, but are too expensive
to be used except in very special and limited circumstances.
Copper is a very malleable substance which has a melting point of 1984.32
Deg F
and a boiling point of 4643 Deg F.
Several of the list's scientists and other knowledgeable persons on the list
have tossed out
figures that are much higher than this as heat levels generated upon entry
into our earth's
atmosphere.
Again, I am no expert when it comes to the mechanics of earth accreting
material from
the depths of space, but it would seem just near impossible for a meteor
composed of
mostly copper to survive til it smacked into the ground (which would change
the remaining
kinetic energy into yet more heat).
All this to say that copper is just not likely to be a meteorite. I do
suppose that if it started
out as a large enough chunk it might be possible to survive til impact.
I've read numerous pieces on asteroids and none are mention as being thought
to be made out of
primarily copper or show the reflected light spectrum of copper.
There are many meteorites listed in the Met Bull as having small percentages
of copper.
None have large to almost exclusive amounts of copper.
I have to agree with Sterling and say that it was most likely something (a
bushing?)
made of copper that fell from an aircraft.
In conclusion, if a copper meteorite existed, I would also look for one made
of lead, or even gold or silver
for that matter but I fear it would share the same fate as the copper
meteorite.
As a side note, Sterling, maybe there was a gold and a silver meteorite that
broke up over
the Ohio and Kentucky area and that's where all the precious metals came
from.

Pete
Received on Sat 12 Jul 2008 01:16:48 AM PDT