Saving Tarnished Costume Jewelry.
this helpful vid.
I have a pair of earrings that I bought last summer, that had started to turn brown.
I rinsed them under running water & applied some toothpaste. After rubbing the toothpaste in small circular motions for a few minutes, I rinsed my earrings under warm water, removing any traces of the toothpaste. Drying them with a paper towel, I then used my blow dryer to thoroughly get rid of any moisture...
& Voila! Like new.