Acetone On Copper Not Good?

, but as far as I know virtually nothing will remove finger prints off of freshly struct copper .

I still guess a soak in acetone for the copper coins couldn't hurt, might even help a little

Acetone is almost completely safe for use on copper coins.

If bright shiny copper is left in acetone for weeks, under bright sunlight or UV light, then a catalytic reaction can take place turning some of the acetone into acetic acid and causing corrosion. Note that you need all three of those circumstances to cause damage. So if you have oxidized copper, or are working indoors away from direct sunlight, or are only soaking the coins for a few seconds (which is all you will need for removal of fingerprint oil) then this reaction cannot take place and you don't have to worry about acetone damaging your copper coins.

The vast majority of "acetone damaged my coins" posts, threads and YouTube videos you might see on the Internet are caused by the acetone removing grime or debris that was concealing corrosion damage that was already present on the coin, hidden underneath the grime.

An acetone you use shall be chemically pure, which may be a problem. I don't know about USA, but here it may be bought in special shops.

Try to drop it on a white paper before use on coins.
Nothing should remain after evaporation

@Sap sums it up very well.

Some time ago there was numerous stories about how Acetone effects Copper if left in Sun Light. So I tried putting Copper coins in Acetone and left in the Sun. I left them there for weeks and nothing happened. Of course those that said it does effect the coins may have been using a different Sun.

Here be a science paper discussing the phenomenon: https://www.sciencedirect.com/scien...468601003590

That's what happened in the lab. The trouble with "repeating the experiment" yourself, like Carl did, is controlling the variables and getting the conditions right. For example, the conditions in the experiment were: place the copper in a beaker with acetone, seal the beaker in a jar surrounded by water so the air inside the jar is 100% humid. Allow the acetone to completely evaporate out of the beaker over 18 hours, while exposed to light.

If you're just sealing up coins in glass jars and leaving them in the sun, then those are different conditions - there's no free access to atmospheric moisture, you're not letting the acetone evaporate away, and the glass jar may be blocking the UV light (or whatever frequency is causing the reaction; the experiment didn't control the light source or radiation frequency). It's also possible that coinage-alloy bronze (slightly impure copper) might not react in the same way as the 99.9985% pure copper used in the experiment.