Let's admit - if one's coins are almost worthless (after doing research!) and if one wants to clean them without the ridicious prices of sending them to the experts to conserve them, I think this might be worth it.

Arranged in order are what I think are from safest to worst ways of cleaning them.

Also if possible, can anyone try to explain the mechanism behind them? I can only understand it terms of acids and alcohol solutions...


0. Personally I would start off with a toothpick to remove most organic stains and such before doing the latter steps.

1. Acetone - to remove awful greenish PVC and other organic stains, like fingerprints etc. I guess it's an alcohol type which dissolves solvents which make it work?

2. Olive oil for copper coins - efficient to tackle verdigris, as it works as a slow type of "acid". I was extremely skeptical of this until I tried it... it does work for minor type of verdigris but for more serious types, you probably need a year or more. But does it have to be extra virgin olive oil to make it more efficient?

3. Vinegar and salt - stronger type of acid compared to the olive oil method

4. Typical cleaning agent like brasso and such - very strong type of acid which not only tackles the problem but strips off metal, hence not a very favorable idea.

Maybe there are more available solutions? I can't think of anything else at the moment.

Clean Coins? such foul language.

Nicely composed list

I have never seen Acetone remove old fingerprints, though. Maybe a really fresh one, but certainly not one that has been on the coin long enough to damage the metal.

Brasso? Hmm ... never thought of that one. I have used Jewelustre as a dip to remove haze and spots from a few proofs that were poorly packaged by some mint, but it's tricky stuff. More than a few seconds in the solution will wreck the mint luster. I would never recommend any kind of cleaning agent on rare or expensive coins because, once it's damaged by the acids, it's ruined forever.

I would recommend sending rare or expensive coins to NCS for professional "restoration" (whatever that means!!!) - I've seen two very nice classic coins before and after restoration, and the difference was amazing.

Has anyone ever tried Denatured Alcohol?

If so what did it do?

Personally I don't like the vingear/salt solution as it's rather corrosive.

Ketchup on an old wheatie will brighten em right up!!

If you approach what is for sale from an effect and composition point of view you have

1) The degreasing agents like soap mixtures and the real dissolving products like
acetone, methylacohol, isopropanol, ethyl methyl keton , etc
First they are solvents and in principle will not attack a coin more then water and heat would So they are safe on all gold coins
Coin stains or dirt will either be hydrophile or hydrofobe in other words they will love water or hate water
If the stain loves water it will only come off with a soap solution
If the stain hates water only a true solvent will work

Best is pure acetone which in hot wheather will leave no trace not even on a gold proof
Or a Soap mixture followed by distilled water
Or any window cleaning mixture followed by distilled water

Be sure never ever to use your fingers or cotton or whatever to assist the dissolving because this will leave marks whereas soap or acetone will leave no mark

2) Then you have the acids and bases like Phosporic acid and Caustic solution
( this will also clean plugged bathroom pipes because it eats anything organic like hair etc )
The acids or bases will in principle remove a layer of the coin and attack the copper or silver in gold
So it is very important not to dip too long
Dips will be recognised by people that have done it
Gold will go more yellow then orange after the dip but will retone in time

A german book on coincleaning reveiled that the costly goldcleaner was nothing but soap

I only have experience on gold

Here in belgium it is denatured by a blue product (colored ethyl acetate )
So the leftovers will be blue spots on the gold coins
For the same price you have pure acetone

Ketchup is very acid
So is Cola which contains Phosporic Acid