Can This Large Cent Be Saved?

The N in united might have some deep corrosion that might not be able to be taken care of. That's a possibility.

Xylene is in the acetone family of solutions - worthwhile for what they do, but completely different in mission than Verdi-Care. It's what you use to get the stuff off the coin that's going to prevent Verdi-Care from working.

Acetone and Xylene will do essentially the same thing, which is remove oils and any other organic contaminants (PVC, Varnish, Glue). Verdi-Care is going to work it's way into the old verdigris, and with the help of a soft brush or rose thorn/toothpick, help to remove decades of old scale deposits. Verdi-Care also does impart a protective quality of coating, though since BadThad is the inventor he can probably impart more info on that feature. For old copper collectors, we used to preserve the coins with Blue Ribbon (no longer made nor will it due too dangerous banned ingredients), from my understanding Verdi-Care does much the same thing.

Acetone is a polar, organic solvent. It works differently from xylene since xylene is a non-polar, organic solvent. Neither organic solvent will dissolve verdigris because verdigris is primarily composed of inorganic salts.

We only recommend using acetone/xylene on coins contaminated with verdigris to remove any organic residues that may be covering or mixed with the verdigris. They have no effect on the efficacy of VERDI-CARE™. However, organic surfaces residues will effect the ability of VC to get to the verdigris and do it's job....hence the recommendation.

Interesting comments on the differences between acetone and xylene:

Since xylene has a primarily non-polar character (as opposed to acetone which is much more polar), and since the 'junk' which accumulates on coins is probably primarily non-polar in character (finger oils for example), logic would dictate that it should be more effective than acetone in removing debris from coins. However, as some of the deposits are probably also slightly polar (PVC residue of example), it is probable best to use both solvent, in sequence.

Of course, neither xylene nor acetone will remove verdigris (as mentioned by badThad). Interesting point he makes, though, that acetone may help slowing/stop its spreading by removing water.

I love learning new stuff, and this thread is becoming a feast.

On another note the experts here have thrown around the terms 'polar' and 'non-polar' frequently in this thread.

So for the benefit of the non-chemists in the crowd here is what they refer to:

The best and most simplistic example is that oils generally are non-polar molecules while water(agua in Spanish) is a polar molecule.

Try pouring some non-polar olive oil in a glass of polar water and note how the oil forms a completely separate layer from the water: technically not a solution. Thus, they will not form a miscible solution.

This is the exact reason why a non-polar xylene rinse on a distilled water-soaked coin, for example, does not make sense or accomplish anything beneficial in terms of removing entrapped polar H2O molecules.

On the other hand, since alcohol is a polar molecule very similar to water, it will form a solution when mixed with water without the formation of two distinct separate layers in a glass.

In summary, all one truly has to remember is one simplistic phrase -

'LIKE DISSOLVES LIKE':

a) polar dissolves polar and

B) non-polar dissolves non-polar

With these concepts in mind you'll better grasp the essential fundamentals of cleaning/restoring coins.

Great thread! Thank you all for sharing. Cipster, nice job with the conservation!