You didn't say what type of metal beads they were so there are a few suggestions but use with caution as the outcome is uncertain if you don't know your metal type.
Tarnishing is a chemical reaction of the silver to the pollutants in the air. This is the same process as iron rusting. To "clean" silver, you want to reverse the tarnish process, rather than remove the tarnish as this can damage the piece.
There are some great cleaning methods listed below in the resource section. You can also make your own cleaning solution:
The best is to prevent tarnishing to occur in the first place. FMG's anti-tarnish paper works like a charm! You can cut them in any size and place inside a zip lock bag.
There are also anti-tarnish organizers and zip lock bags. All of these work wonders and save you heaps of time cleaning and polishing.
- Kristal Wick, Designer, Author, Jewelry Making Expert and Swarovski Ambassador