Remove a spot from a Lincoln Cent?

ellewood

I have never attempted to remove a spot from a coin. Wondering if any of you out there have any ideas for removing a spot like this? Do spots like this usually grow back after they are removed? It's not a crisis if I ruin the coin...I'd almost rather take the chance than stare at this "tumor" on Lincoln's forehead....

Any ideas would be greatly appreciated!

T

Keyrock

Having talked to a few dealers who have tried this, it will grow back. Even NCS processed coins will have an 'off' look to them and it grows back with time. If you don't like the spot dump the coin. Copper is too reactive and you will just lose every way on the coin.

Rich

Edited for typo

Steve27

Learn to live with it or get rid of the coin, because that spot and the one on the reverse are permenent.

jacktheknife

Why would a spot like that return? Isn't that spot simply a product of a chemical reaction? Let's say, just for example, that it's a small spot of CuSO4 or some other copper compound. Then it is removed; conserved if you will. There is no more reactant around (SO4=, or other anion), so how does the spot return?
Not that I don't believe those that have posted ahead of me, I'm just wondering how it happens. It really doesn't make sense. If you really know that it is a waste of time to remove the spot because it will simply come back, tell me how it happens. I'd like a little more concrete explanation other than "It does".

Jack

clackamas

I don't think it will necessarily come back. Usually there is a piece of something causing the corrosion spot. you can usually remove the problem causing the spot with something like a rose thorn. I had no idea you could actually remove the spot, but don't think it would come back unless the cause was still present.

coolkarma

<< <i>Why would a spot like that return? Jack >>



I've also wondered that. I've come to believe that it depends on the cause of the spot. If there is a contaminant "on" the surface of the coin that reacts with the copper, then one can remove the spot and the contaminant. If you remove all of the contaminant, the spot should not return. However, if the contaminant is "in" the surface of the coin (i.e., part of the planchet), then you are out of luck. You can remove the spot, but some of the contaminant is still present. In this case, eventually the spot will reappear. At least those are my current "beliefs".

jacktheknife

MANOFCOINS,

A description I can truly appreciate and understand!


Brian and coolkarma,

I think we are all talking about a similar hypothesis. Brian, I also don't know how the spot would be removed. However, if it could be removed (without inflicting damage to the coin) it should not come back unless there is still something there reacting with the planchet (coolkarma's example).

So, the next question is - Are "carbon" spots contamination "on" the coin or contamination "in" the coin?

Jack

DMWJR

"on" the coin.

Keyrock

If the surface of the coin is altered causing the reaction to occur and thus the formation of a spot, a chemical method is going to be used to remove the spot. Using copper sulfate in the example, once the area is cleaned/curated the area of removal is highly reactive. You typically need to passivate the surface making it unreactive. If the impurity is in the coin, humidity or some other environmental stimulus caused the spot to form. By removing the spot you have just removed the visual distraction not the root of the problem.

I have talked to a few dealers (Who specialice in coppers) off line and they have mentioned they have delt with coins treated by NCS. The coin comes back clean, maybe with a off color, and the defect grows like a cancer over a few months, looking worse than pre treatment.

I look at it this way, it is a cancer that can grow or stay malignant. Cutting it out doesn't mean you solved the problem, just delayed the inevitable.

Rich

jacktheknife

Rich,

Sounds like your vote is "in" the coin. Good point about the reactive surface after spot removal. That may be a very important point in understanding how the spot returns.

Jack

iras4

<< <i>I have never attempted to remove a spot from a coin. Wondering if any of you out there have any ideas for removing a spot like this? Do spots like this usually grow back after they are removed? It's not a crisis if I ruin the coin...I'd almost rather take the chance than stare at this "tumor" on Lincoln's forehead....

Any ideas would be greatly appreciated!

T

>>



There's an individual I know who has developed some specialized tools to remove spots. No chemicals are used, and the fellow has a very steady hand such as a skilled watchmaker might have (his Dad was a watchmaker before him). Over a period of HOURS, he gradually shaves off the spot and what's left will be a grayish spot the size of the original. He's had these coins then regraded, typically by PCGS. The color of the coin is not changed and the remaining gray spot is not reactive. But, that said, humdity of the type found in most fire retardant safes is the real foe, as the safe continually emits water vapor into its interior and it finds its way onto the coin, causing the mischief.

I keep all coins I sell in Intercept Shield boxes prior to sale and when I ship I also include one of the smaller IS treated capsules that encase the slab. That seems to work, as the material in the Intercept Shield boxes & inserts is pure copper and it's the copper that reacts before the coin is affected.

I believe that slabbed coins have the problem more than raw ones, as there is so little air circulation around the coin that microscopic beads of water condense on the surface of the coin.

I should add that the fellow that does this work is VERY EXPENSIVE, it will NOT work on all coins, particularly if he thinks the surface is pitted or eroded from the spot and he doesn't gurantee that the coin wil re-slab, but most all will. Again, you all know that even if a coin came from a PCGS holder, once its broken out and resubmitted, there's always the possibilty that it will return in a body bag, and that might have nothing to do with the spot removal, which leaves no tell-tale evidence under 20X magnification.

I've never used this fellow myself but I've seen his before and after work and its impressive. You do NOT wind up with a pristine surface under the removed spot.Therse' always a grayish area underneath. Coin is much more presentatble, however. I agree with the statement regarding NCS conservationof copper and bronze coins. From what I've seen after conservation of such coins, the reults a few months later are not generally appealing.

Ira

Steve

<< <i>
I agree with the statement regarding NCS conservationof copper and bronze coins. From what I've seen after conservation of such coins, the reults a few months later are not generally appealing.

Ira >>



If Ira and others comments concerning the after effect of NCS conservation are correct, then I would think NCS and NGC will take a negative hit business wise. Why send coins to them for conservation? Steve

iras4

<< <i>

<< <i>
I agree with the statement regarding NCS conservationof copper and bronze coins. From what I've seen after conservation of such coins, the reults a few months later are not generally appealing.

Ira >>



If Ira and others comments concerning the after effect of NCS conservation are correct, then I would think NCS and NGC will take a negative hit business wise. Why send coins to them for conservation? Steve >>



Well, there IS a good reason, Steve. I've seen some excellent results on silver coins and even on copper spot removal on gold coins. I've just not been pleased with bronze and copper conservation on the ones Ive seen. The surfaces are just too reactive to predict what the ultimate result will be.

OTOH, they have made some badly toned silver coins much more marketable and I've seen only mixed results with nickel coins. Not too surprising there, as nickel coins are about 70% copper.

Ira

majorbigtime

Take a wooden toothpick, soften the tip a bit (just push it on a hard surface), and carefully try to push the 'lil buggar off. It's worth a shot on a coin like this. I'd go for the buggar at the bottom of the right wheat stalk too (I'd probably start there).

Like you, I HATE spotted copper or nickel..

pcpro

Hi

Copper sulfate comes in 2 forms; a white powder and blue crystals.

Common copper compounds that are black include copper oxide and copper sulfide.

Once copper metal forms an "active site", there's plenty of oxygen and airborne sulfur to create more of these compounds.

It's very likely the spot will "grow" again.

Walt

Boom

Get the scalpel...Steady there Doc!

jonesy

Dang!! I was hoping for an easier cure.