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copper wire, copper coins

updated sat 14 sep 02

 

Earl Brunner on tue 10 sep 02


Beg to differ Vince, but U.S. pennies are no longer "copper" they are
copper colored, possibly copper coated but they are no longer fully
copper. I think that they are Zinc or some kind of alloy. I know that
it is now considered more dangerous for children to swallow the newer
pennies, because they react more dangerously with digestive acids than
the older copper ones. They have been making the newer pennies for at
least ten years I think. The newer pennies corrode different than the
old copper ones as well, they pit faster.
In fact I checked the mint
http://www.usmint.gov/about_the_mint/index.cfm?action=coin_specification
s
pennies are copper plated zinc.

Earl Brunner
mailto:bruec@anv.net
http://coyote.accessnv.com/bruec


-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG] On
Behalf Of vince pitelka
Sent: Tuesday, September 10, 2002 5:59 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: copper wire, copper coins

> Don't know if you were using a US penny, but they're made of aluminum,
and
> that explains why it "ate" everything. These days "copper" penny is a
> misnomer.
> Ditmar

No, that is not correct. Copper pennies are copper. Quarters and dimes
are
copper, clad in a very thin layer of silver or nickel-silver. The US
has no
aluminum coins. When you find foreign aluminum coins, you can really
tell,
because they are so light-weight.

vince pitelka on tue 10 sep 02


> Don't know if you were using a US penny, but they're made of aluminum, and
> that explains why it "ate" everything. These days "copper" penny is a
> misnomer.
> Ditmar

No, that is not correct. Copper pennies are copper. Quarters and dimes are
copper, clad in a very thin layer of silver or nickel-silver. The US has no
aluminum coins. When you find foreign aluminum coins, you can really tell,
because they are so light-weight.

An aluminum coin would just turn to highly refractory alumina, and would sit
on top of the clay without doing a thing, other than soaking up some glaze.
Best wishes -
- Vince

Vince Pitelka
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Home - vpitelka@worldnet.att.net
615/597-5376
Work - wpitelka@tntech.edu
615/597-6801 ext. 111, fax 615/597-6803
http://www.craftcenter.tntech.edu/

iandol on thu 12 sep 02


Dear Earl Brunner,

If U.S. pennies are copper coated, have a Zinc alloy body and come in =
contact with acid there will be an immediate chemical reaction if they =
are scratched. A classic case of electro chemical corrosion.

Best regards,

Ivor Lewis.