Olive Oil?

I believe most here on this forum will say don't do it. Use it in your cooking.

Olive oil is used quite a lot in the process of cleaning otherwise unidentifiable ancient coins. I have used this approach myself with success in the cleaning and preservation of ancient bronze coins.

There is a downside unfortunately, olive oil is slightly acidic.

Although olive oil CAN in fact, help with the cleaning and preservation of ancient bronze coins, it can darken them considerably.
This ain't good with brilliant uncirculated and modern proof coins, they can darken as well.

So don't do it.


NOTE: If you wish to preserve brilliant uncirculated and proof coins, they can be sprayed with clear acrylic lacquer,
Most collectors haven't the nerve to do this, but it works. I don't have the nerve to do this, either.

However, I have made ONE exception. Way back in 1964, I obtained a few newly struck half dollars. The coin that I sprayed is as good as the day I sprayed it. All of the others have patinated to a greater or lesser extent.

The lacquer can be removed with acetone, but I won't be doing this on the only coin I have preserved in this way.

Hmmmm..as weird as it sounds I like the lacquer concept. The Mint should spray their ASE's with it before shipping to cure the milk spot problem

Now let's see if we can get the TPG's to grade a lacquered up coin

I should add I would never have the stones to do it...it just sounds good

I tried olive oil on two coins. One was a large cent, and the other is a civil war token that were showing some greening. It didn't help very much. Probably wont try it again. The only reason I did, is my local coin dealer suggested it.

That wouldn't do anything as the spots are in the metal itself. If memory serves, it's a rinsing agent or the like that is on the coin when struck.

As mentioned, olive oil is acidic, so NOT a good idea. It will not protect the coin, it will eat away at the coin. Like the others said, it works to remove stuff from buried coins, but that's the only time I would use it.

Spraying a coin with anything to protect it is not something I would do. Simply putting the coin in an air tight protects it from just about everything. 2x2's and coin tubes will do a good job as well. Simply storing the oin properly will protect it just fine.