My Grandmothers silver teapot.

Hmmmmmm......I deal with a lot of antiques, in my home and buying and selling, of which my favorites, are silver. A cheap and easy way to clean silver itself, is the aluminum and baking soda trick. I found a site that lists a recipe, but the one I use is almost as simple. Take a sheet of common aluminum foil and put it in the bottom of your sink, add the hottest water you can, then add a cup of baking soda and your silver items. Do not use RUBBER GLOVES, use COTTON GLOVES for handling your silver (won't leave finger prints and rubber gloves contain sulfur), which will leave nasty finger marks on your silver. You should be able to watch the silver tarnish come right off, if any remains, simply rub off with a soft cloth or micro fiber cloth and rinse and dry. You can actually do a number of pieces with this recipe. As to cleaning the inside of the pot, I would try a LITTLE paste of baking soda with a bit of warm water and scrub lightly, this is for the INSIDE of the piece ONLY! Rinse well and dry by hand. DO NOT USE BLEACH unless you like scarring your Grams precious tea set! If you have a good quality silver tarnish paste, you can try rubbing it on the inside to remove tea stains, light oxidation, and guess what I am stains. But baking soda is probably your best bet. Please try in a small spot first to see how it works before going all at it. It sounds as if your Gramms tea set may have some other base metals in it and with that, comes some different ways of cleaning it. At least with these formulations, you shouldn't go wrong. Hope this helps you! Good luck!