To Clean Or Not To Clean!

It is possilbe to correctly clean or conserve an ancient coin, many have done it but learn about it before trying. It's good to experiment on cheap ancient coins before trying it on a valuable one. There's posts here on CCF about it and Youtube videos you can watch. Do not use anything abrasive. Many soak ancient coins in solutions like distilled water, olive oil for weeks or months. Many ancient and modern coins found in the ground need to be carefully cleaned besause of the encrustation. A bried soak in acetone may help.

The green areas on the reverse look hard and stable, it may or may not come off and you could make it worse trying to remove it. If crud is on the surface of a coin it's possible to remove it. But if it goes deeper into the coin that's a problem. The green stuff is called vertigris. I've used Verdi-Care to improve the appearance. When green stuff on ancient coins is powdery it could be active bronze disease which needs to be treated to stop the corrosion.

Your coin might clean up okay...but it might look worse. It helps to know what you are doing before trying to clean a coin. You should practice on some culls to better understand what will happen. I used to clean lots of ancients; but now only clean occasionally. Here are a few that I have cleaned --

Well done.

I don't recommend that inexperienced people clean coins with chemicals; but my most effective chemicals are carbonates with three different pH's-- sodium bicarbonate, sodium sesquicarbonate and sodium carbonate. Occasionally I have used electrolysis...once again you should not attempt unless you have some experience.

Here are two of my favorite products for cleaning green...cleaning time varies depending on condition of coin and strength of solution. Don't ever try to clean a coin unless you understand you can make it worse. Remember you can't undo it.

here's one that I soaked in ammonia (maybe 10% solution) for about 30 minutes and then scrubbed with a denture brush...they have firmer bristles than a normal toothbrush.





some of my cleaning chemicals

I never used ammonia, only sesquicarbonate and only on active bronze disease. It is slow to remove deep corrosion, sometimes I have to mechanically remove the upper layer.

Victor, is there some advantage in using ammonia?