What you guys think about using this for cruddy ancient coins without potentially disturbing the surfaces?
It will probably turn your bronze coins into Gatorade. I don’t know about the silver coins. Lighthouse coin supplies sells cleaners for silver coins, I think I would have tried them first.
I used to mess around with uncleaned lots in the early 2000s and tried using an ultrasonic with very little success. Repeated soaks in Distilled water or olive oil followed by brushing and manual removal seemed be the only thing that worked consistently, but it was very slow. Eventually got bored with them. Still have about 100-200 uncleaned and partially cleaned sitting around in a box.
I was in the process of typing more or less that same thing that Oldhoopster wrote when his message appeared, so I'll just second what he wrote.
I developed a cleaning process over the last 40 years but my posts normally get killed as the Moderator suspects self-promotion. Contact me privately and I will give you my two criteria for ultrasonic cleaning remembering tough soils over sensitive surfaces epecially for bronze alloy pieces. I do not collect ancients other than helping my daughter purchase greek coins when we meet at the NYITL and when I recently was in Israel - Jewish Revolt pieces. In some ways its complex as I had to weed out what worked and did not work. It helped I was an R&D chemist for awhile in Industrial Cleaners and I have M.S. in Chemistry. BTW the current VerdiCare is garbage, the current Coin Care is perfumed nonsense and all others are copper brightness imposing hairlines ... OH NO ... here comes the AX! LOL John Lorenzo Numismatist United States
I have an ultrasonic cleaner and used it quite a bit for bronze coins. My opinion is that you shouldn't use it for ancients. Short bursts of cleaning is ok, but it doesn't take long to strip the patina. Of course, people will want to try it for themselves, so use cheaper coins that you don't mind messing up and then find someplace in your garage to store the ultrasonic cleaner...probably next to the rock tumbler that you heard could be used to clean coins.
I'm surprised to hear that it will strip the patina. All the comments I'd heard in the past were the opposite, that it didn't do much of anything except maybe remove some loose dirt. What kind of liquid do you use for the bath?
I believe that I used distilled water. As I said, short bursts were OK, a bit longer and shiny spots started to develop. Another problem is that the coins bounce around unless you hold each one on a hanger system. If a coin is fragile, it is real easy to do more damage.
