Spent most of my working life (as a histologist) working with these solvents and I'm still here, and I've worked with lots of things far nastier Wear gloves, use plastic forceps, use them outside or in a well ventilated area, avoid naked flames, and you'll be OK NB avoid nail varnish remover, can have unknown additives, my local pharmacy sell small (50ml) bottles of pure acetone, with is ample to soak a couple of coins in. Acetone evaporates quickly, so use a jar with a lid if you are planning on a soak rather than a quick dip Don't know where one would buy small quantities of xylene though, I used to buy it 25 litre drums, but if you do locate some ensure it is marked "sulphur free" if you are going any where near coins. David