On 02/27/2011 06:02 PM, JIMMIE wrote:
On Feb 27, 4:14 pm, wrote:
On Sun, 27 Feb 2011 02:08:03 -0600, dilbert firestorm

wrote:
there's a website that showed you how to remove zinc from a copper
plated penny.

end result, all the zinc was gone and you got a very thin piece of
copper penny left over.

don't remember which acid they used.

It might have been an episode of Modern Marvels: Acid.

IIRC they demonstrated this and mentioned just how thin the cooper was
over the zinc.

Spend a night at the Waldorf Astoria. One of the services they offer
there is to clean and polish your coins. Paper money is cleaned and
pressed. All included in the cost of the room.

Jimmie

The Mark Hopkins hotel in San Francisco used to do a similar thing,
except they washed ALL the coins they expected to give out as change for
the next day. Theoretically, you could buy a candy bar at a concession
stand there and expect shiny coins in return. Kind of put a smile on
your face for the rest of the day.

There was a photo of the coin washing machine in the SF paper once. It
was a horizontal, stainless steel screen cylinder about 1' in diameter
by 2' long that rotated slowly in a tub of soapy water. The cylinder was
half-filled with coins and lots of lead shot. In effect, an extremely
low velocity shot blasting machine.