How do you clean tarnish off a Tiffany and Co bracelet and necklace?

I am wondering if there any home remedies for cleaning silver. I have a set that I got in England and it sat in the Tiffany %26amp; Co blue box for 5 years and is almost completely BLACK with tarnish. I've tried regular jewelry cleaner, even left it in there for 30 minutes then scrubbed it with no luck. What can I try to get the tarnish off?|||Go to your local kay or jared jewelry store and pick up the jewelry wipes they carry. they are in a red box and are about 7 bucks! You will have to rub for a little time, but it will look as good as new! Hope this helps!