Any tips on how to clean a coin like this?

[Josiah Y]

I have several coins with a flaky looking patina like the one below. I feel like the green patina is actually obscuring the detail and I was wondering what you guys would think is the best way to clean coins like this?

[Nathaniel N2]

I'm afraid that coin will never look better than it does now. Removing the patina will remove the detail that still remains. If you really like the coin but want it to have more eye appeal just for you personally, you might look into some fully reversible techniques to mask the exposed metal such as a green wax on those areas or a fully reversible acid free paint such as is used in painting conservation, not oil based and easily removable with a solvent like distilled water nothing stronger. That said, if it was me, I would just wax it and keep it as is.

[Nathaniel N2]

With the patina as is I can identify the coin type, mint, officina, reverse type and see much more. Don't remove the patina!

[Josiah Y]

No worries, I don't plan to remove the patina. I'm planning to do DW soaks and using a nylon brush only. I think even toothpicks would too much for this coin, especially on the reverse. I have many coins with a flaky patina and so far I've found that some flake off even during the DW soaking phase alone. The only thing I have found that works is to practice abstinence and just leave it as is and was wondering if the more experienced people here had any process they use on coins like this.

[SC]

Yup, these can be very frustrating.

I always search through and pull out any coins like this before doing any water soaks as even that can harm some.

I then gently poke and prod with a toothpick to see just how stable, or not, the remaining patina is.

If fairly stable, then one can often clean off some dirt with soft toothbrush and toothpick, or even metal pin in some cases, then wax and store.

If unstable, then there is little that can be done.  Sometimes rubbing the coin gently between thumb and fore-finger can help - believe it or not. Waxing can help, if it can stand it, as it reduces friction on it later.  Such coins also often do better in a tray than in a flip or envelope.

SC

[Ron C2]

That coin isn't going to be improved with dw soaks, in my opinion. The dark areas are exposed flan core, not dirt.

It it were mine, it heat dry it for a few minutes (lowest temperature in a countertop oven) let it stand for a week in a dry place, and then ren wax to preserve what's left.

[Joe Sermarini]

I agree with Ron.

[Virgil H]

I am curious, what is a countertop oven?

Virgil

[Jay GT4]

It's like a toaster but an oven

[Virgil H]

OK, thanks on that, I am visualizing what I know as a toaster oven. That has to be similar. I guess there is no reason not to do this in a normal oven, as well, just less efficient energy wise.

Virgil

[Ron C2]

OK, thanks on that, I am visualizing what I know as a toaster oven. That has to be similar. I guess there is no reason not to do this in a normal oven, as well, just less efficient energy wise.

Virgil

You've got it! The goal is you want virtually no moisture in a coin before you wax it, or you could have BD form under the wax film.  Heat is a great wat to suck out the wet.