To Rinse Or Not To Rinse...that Is The Question?

the acetone is to clean the rinse is to get the acetone off.

I have also heard of people doing the final rinse with acetone to make sure there is no residue of what the initial acetone removed from the coin

MontCollector, you did good if you really procured 100% acetone. Outside of specialty chemical supply companies, it's usually about 97% (natural grade). Most of the remainder is water, but also contained are non-volatile substances at trace levels. Acetone is such a good solvent that it's difficult to keep it pure. Evaporate some "clean fresh" acetone on squeaky clean glass and you may notice a faint white film. I don't know exactly what this stuff is, but it would coat a coin if not washed off before the acetone evaporates. I work in a lab (bottle washer emeritus) and use several rinses of distilled water then pure ethanol for spot-free scientific glassware. I haven't tried it, but a good denatured alcohol would probably work as well for coins. Just do a spot-check on glass first.

Relax. Just use the acetone. It is fine.

It's a simple test. A drop of acetone on glass - or better, on a mirror. If there's no residue you're good. If there's a film, get acetone from another source. It's dangerous to assume; I've learned that lesson many times.

I'd rinse with distilled water. Acetone potentially has trace acids or organic solvents dissolved in it. You are not capable of determining if it is pure by casting it onto clean glass as the amounts of contaminants that could cause harm are too low to see. If you can see a film, the acetone is horribly contaminated and probably shouldn't be used at all. You should never use technical grade acetone (97%) for numismatic purposes. I run an analytical laboratory and would not let that crap into the facility even to fill wash bottles.