Cleaning question

[Zeppelin]

I have heard a lot about cleaning some pennies by soaking in acetone, and then letting them air dry on paper towel without rubbing. I haven't heard anyone say for how long to soak them for though. What is the recommended soak time? Thanks everyone

[Roller]

There is no proposition on time. It all depends on the condition of the coin and what is adhered to it. Except, perhaps, on high mint state coins, in my experience it does not matter. I have had some coins soaking for days, having forgotten, with no adverse consequences. Acetone, while it may not harm the patina of the coin, will harden adherent material on the coin. Just soaking will not remove most adherent material. Rubbing will loosen the adherent and likely scratch the surface. That is why I opt for ultrasound cleaner without chemicals, just hot water, after soaking. Also, it may be advisable to soften the adherent, rather than hardening it with acetone or do both, depending on what works. I use verdicare for softening. In either case I follow with the ultrasound hot water.

[GrumpyEd]

Acetone gets certain junk off of coins.
It isn't really cleaning, it's more like rinsing.

In general, it probably won't do too much other than get certain junk off, it won't get most stains off, it won't make an RB into a red. It might slightly mute the color on some red cents.

When you hear people talking about dipping and worrying about exactly how long to dip, it's often chemical dips sold for coins not acetone. Some of those do remove some metal. Some people can do it to MS or PF copper but they know how or they'll mess up the coins. Even ones not messed up may mess up over time. Dips like that are more accepted for silver but even then if done too much it can damage the coin plus they'll tone again and if they're dipped over and over they get damaged, some people prefer never dipped to a blast white dipped silver coin.

And then there's brutal cleaning, I'd never do it unless the coin is already a problem coin.

And then there are dirty crusty low grade circs, I remember Coop had some pics of ones cleaned up pretty well with an old toothbrush, in reality most crusty low grade circ coins have already been abused so it works pretty well, look at his pics if you can find them. The same brushing would ruin an unc coin but it might clean up a low grade beat up junk bin IHC and not harm it.

Verdicare might help with coins with some corrosion or verdigris.
Soaking in mineral oil might help with corroded or dug coins.

There is no single answer on cleaning, the best one is don't mess with coins that do not already have a problem, it rarely helps.