|it does looks cleaner in person...|
Simple fill with hot tap water and plop in a polident tab. Let it sit for an hour and rinse out. You may go back in an scrub any left over stubborn stains or let it be. This works on modern mugs as well and pretty much leaves no grime behind.
So this is not vintage but if you cook with a crock pot you know there is always cooked on food even if you use a liner bag. By adding in a polident tab to your overnight soak you can almost get away with not having to scrub it, just rinse with a cloth.
I pretty much soak every new brooch or earring a bring home in polident. It gets in all the crevasses of rhinestone jewelry and cleans up enamel easily. I have never tarnished a piece but to be safe I would not soak for more than an hour.
Anybody else have any good and easy tips to clean up vintage?