No passwords, No popups, No cost, No AI:
we earn from 'affiliate link' purchases, making the site possible

Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Adver-
tise
Help
Wanted
Current
Q&A's
Site 🔍
Search
ted_yosem
Sound technical content, curated with aloha by
Ted Mooney, P.E. RET
Pine Beach, NJ
finishing.com -- The Home Page of the Finishing Industry

  The authoritative public forum
  for Metal Finishing since 1989
  mfhotline


  -----

Removing zinc coating from a copper penny without hurting the copper





2006

I have a very old copper penny, which some collector (many years ago) coated in a silvery metal (I think zinc), I assume thinking that by coating it he would be protecting it. By removing the coating, the value of the coin would greatly increase, but I want to remove it without harming the copper underneath. Was there a procedure (during the 1930's & 40's) to coat coins and is there a way to remove such a coating?

Jay Cleland




2006

The usual rule is don't do anything to it. I am surprised that a penny from the 30s or 40s is valuable. Or maybe you are saying the collector was from the 30s or 40s but the coin is much older than that. Please tell us what coin it is and what you think it could be worth.

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey



2006

It is a 1909 S VDB penny, and would be worth about twice as much without the coating (over $1000)

Jay Cleland [returning]




2006

Thanks. Sorry, I've never heard of that preservation method. A quick dip in muriatic acid this on eBay or Amazon [affil links] should make short work of a zinc coating, but I don't think I'd do it to a valuable coin.

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey



2006

According to the 1980 Metal Finishing Guidebook (an oldie but goodie), zinc over copper alloys can be stripped by 1) Warm dilute hydrochloric or sulfuric acid, 2) 10-15% ammonium nitrate, or 3) Hot sodium hydroxide solution.

Chris Jurey, Past-President IHAA
Luke Engineering & Mfg. Co. Inc.
supporting advertiser
Wadsworth, Ohio
luke banner



2007

Sir

I think what has happened is years ago as a young lad we would take mercury out of a thermometer, and rub it on a penny to make it look as if it was steel. not very smart because mercury is poison. if you want to remove it do not use anything that would be corrosive to the coin someone had told you to use sulfuric acid don't.the old miners years back would pour mercury in their gold pans because it would collect the small particles of gold then the miner would have a problem of how to get the gold out and save the mercury. take a potato cut in half. now take a spoon and dig a hole in the potato put the penny in and put the potato back together wrap it in aluminum foil. start up your barbecue and place the potato on the grill after the potato cooks the mercury turns into a deadly gas don't stand around your BBQ the potato collects the mercury leaving the penny behind now throw away the potato . see if this works for you please respond

Don't eat the potato a lot of old miners lost their life by eating it.

Raymond Tuggle





(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

Finishing
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g,
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"