Golden picture frames - how to get them shiny again

If you are at all a person who likes flea markets, then this is for you. If you find an old golden picture frame which is often black and not shiny at all anymore, here is a tip how to get it shiny again.
Just put some regular salt in a bowl and add only a little bit of water to it to make it damp.
Then use a damp sponge and put some salt/water mixture on it and rub the frame with it, you need some muscles to do that. This way your old golden picture frame looks shiny again.