Simply mix a teaspoon full of baking soda with warm water... just enough to make a paste. Spread it on the pin, rub gently, rinse - - - et voila!
Larger pieces, such as silver plates and serving dishes are easily cleaned by placing a sheet of aluminum (your aluminium) foil... shiny side up in a glass dish of some sort. place some hot water in the disn... enough to cover the item being cleaned and then add a small palm full of baking soda. When it's dissolved, place the piece to be cleaned in the solution and walk away... just walk away. Leave it for an hour or so, the tarnish will have transferred to the foil liner... (It works better if the water is really hot)...