| Author |
 Replies: 9 / Views: 7,948 |
|
|
Pillar of the Community
United States
592 Posts |
Is there any way to remove carbon spots from proof coins? Or from any silver coins for that matter?
|
|
|
|
Bedrock of the Community
United States
19944 Posts |
Not without ruining them.
|
|
Pillar of the Community
 United States
592 Posts |
Thanks. That's what I figured. What causes them?
|
|
Bedrock of the Community
United States
20753 Posts |
I don't think anyone really knows for sute where they come from, how they appear, what they really are. And that is one of the problems in removing them. Unless you know for sure what something is, it is really difficult to know how to do anything about them. A sort of example is if you got a stain on your cloths and tried some methods of removal without knowing what it is, you could make it worse. And that has happened to cloths and also with those spots on coins. I've tried numerous ways to get rid of those on a coin and usually end up making a mess of the coin. Acetone, Baking Soda/water solutions, lemon juice, jewlery cleaners, Laquer thinners, mineral spirits and lots more have failed. May sound funny but a Butane Torch did work but sure made the coin look oddly like it was on a Bat-B-Que grill.  |
|
Valued Member
United States
307 Posts |
What color are carbon spots  |
|
Bedrock of the Community
Australia
21786 Posts |
I have a rather nice Indian Edward V11 rupee of 1908 in AU. Very disappointing with black staining, which I guess is just a gross form of carbon spots. I have failed just like just carl. The best result, which was still a failure, was to gently rub the coin with soap between my fingers.
I think the black stuff is silver sulphide, and on 20x magnification, has eroded the surface of the coin slightly, similar to verdigris.
|
|
Bedrock of the Community
United States
19944 Posts |
Quote:
think the black stuff is silver sulphide, and on 20x magnification, has eroded the surface of the coin slightly, similar to verdigris.
Yes, you have a sulfide layer (toning) that is very mature. Black is the last stage before the coin starts losing metal to the process. Once it's there, the coin is a goner. You can dip it using the classic acid-thiourea method, but the coin will look obviously cleaned. Lincoln Cent Lover!VERDI-CARE™ INVENTOR https://verdi.care/
|
|
Valued Member
United States
307 Posts |
Is carbon spotting progressive in nature or can it be treated to eliminate further spotting.
|
|
Bedrock of the Community
United States
20753 Posts |
Quote:
Is carbon spotting progressive in nature or can it be treated to eliminate further spotting.
Basically any toning, staining, corroding, etc on coins can be stopped if no air, gasses, moisture can get to them. That is why so many place coins in air tights. I put all my Albums in Zip Lock bags to keep ourside sources at a minimum. Only a vacuum will stop all such reactions. |
|
Valued Member
United States
307 Posts |
Since I just realized I had a problem with spotting I started putting my coins in resealable baggies for some protection, I use gel packs and now a dehumidifier. It has really gotten my attention.  I also have treated some coins with Verdi-Care hoping to protect them from toning or spotting. Thanks for this help. |
| |
Replies: 9 / Views: 7,948 |
|
Posted 02/25/2011 5:41 pm
