Hello everyone, I wonder how many members will chastise me for doing this little experiment? As many of you know I am an avid Metal Detectorist. Recently I dug up some neat coins that weren't in the best of shape. Years of soil, dirt and clay took a toll on them For example.. These two Indian Head Cents and a V Nickel are covered in crud. I soaked them overnight and I was not able to achieve a good cleaning. I googled ways of cleaning off crud and found a Metal Detecting forum that gave some advice on how to do so. One technique was to soak them in Olive Oil. I am to take the coins out once a day and gently rub with a cloth then place them back. The process will take several weeks to get all the crud off. I found a small container with a raised bottom that when the coins are place in they will be lifted in a way the the Olive Oil will saturate both sides. It contains 2 IHC's, 1 V-Nickel and 2 3 Wheat Cents.. I of course covered them in case I knock the container over.. I'm a clutz A few weeks ago I soaked a IHC in vinegar overnight and I hated the result. The crud came off but the Cent turned orange Any feedback, opinions, comments are welcome!
I was taught Olive Oil by a TPG personality ... The green verdigris absorbs the oil and then basically "pops off". works pretty good. but need a technique to prevent it from coming back. but then you get threads like this .... https://www.cointalk.com/threads/1806-draped-bust-half-cent.369889/page-3#post-5130483
I'm not just trying to get the green stuff off. It's the cemented crud that looks like a jackhammer is needed to remove it.
I don't know, never had good luck with those coins except two IH stuck together. Might be worth try anyways.
Olive oil was recommended when I played with uncleaned ancients 15-20 years ago. Had mixed results. Olive Oil is supposed to be slightly acidic (if I remember correctly), but I wouldn’t expect it to be a problem with your detector finds. The prevailing wisdom at the time was to use a toothbrush with cut down bristles to brush the coin between soaks. While this may seem harsh, it seemed to help. I tried to brush the cruddy areas and stay away from the coin surfaces. Once again, it didn’t appear to cause any problems on the crusty ancients. This is what I would try Soak in distilled water Brush Repeat until water is clear Acetone (If you don’t get anything coming off or softening after 30-60 min in a closed jar, it probably isn’t worth continuing) Water rinse Brush Olive oil soaks You can also try things like a pin vise or dental tools for hard stuff. You need to use a microscope and it requires patience and a steady hand, but some of the ancient people did a really nice job (however, I didn’t have the patience and that was one of the reasons I quit messing with them). You could also play around with some sulfur compounds (like deller's darkener or powdered sulfur) to retone your HC. The coins are already shot, so a more aggressive cleaning to remove the crud and retoning might be a viable option to make the coins look nicer. They're not going to fool anyone thinking they're original surfaces but IMO, it might be worth trying on some of the copper cents
It depends on how valuable the underlying coin is and your tolerance for ruining the surface vs removing the encrustations. I tend to clean my low value ancient coins with harsh chemicals and mechanical tools - I value strong details over a natural patina, basically. lye removes verdigris pretty effectively; any blue deposits will be taken off by vinegar and brown tends to be removed by sodium thiosulfate
I wouldn't use olive oil, as it is acidic, and anything acidic will corrode copper (as will vinegar for the same reason). If you're trying to get rid of cemented crud, you might have better luck with an ultrasonic jewelry cleaner. Collectors of ancient coins recommend soaking in sodium sesquicarbonate. It may not get crud from the ground off, but it will get rid of green corrosion.
https://www.metaldetectingworld.com/cleaning_preservation_coin.shtmlTake a look at this website, I learned a lot here while doing my own experiments. Currently using mineral oil on a 2¢ piece. Mineral oil doesn't turn a copper dark like olive oil but it takes longer to do the job of softening crud.
Very interesting topic, views, and opinions. Good luck pattyman and thank you for the post I learned a lot.
paddyman I would soak it in olive oil for a few days....What I have noticed the olive oil will darken the coin to where it should be....Some cents and nickels that I cleaned myself and I had cleaned them too much...Their color was very very light. Could hardly even see the date....Those coins took more than a few days in the olive oil....I forget exactly how many days but it was over a week. The nice thing was they ended up getting their color and "tone" back. Worth a try
Thanks.. They aren't valuable coins so it won't hurt.. I'm keeping them in oil. I will post the results when I feel they have marinated enough
Update.. Late but better than never. The olive oil did nothing for the appearance of the coins. I took tbem out a week later and nothing occured. Oh well I tried. Thanks everyone!
