WELL it is free if you have a few kitchen items handy. If you don't have these items lying around in surplus - sheesh go buy some baking soda and salt! Besides anything that doesn't involve toxic chemicals is a must! So gather the following items and get ready for some shiny metallic fun!
1) Boiling water - enough to cover item
2) 1 tablespoon baking soda (per cup of boiling water)
3) 1 tablespoon white salt (per cup of boiling water)
4) 1/2 cup white vinegar (per cup of boiling water)
5) 1 sheet of tinfoil, shiny side up
6) plastic bowl plastic tub, or plastic storage box
7) Polishing cloth - towel, old cotton T-shirt or natural fiber cloth
I got this idea from this article on the Clean my Space Blog - but the recipe does not have to be exact - because I did a large silver antique bowl I had to use a lot of water to cover it….and well….I am too lazy to measure everything out…but not to worry it still worked. I placed the foil shiny side up covering the bottom of the plastic tub. Then sprinkled a generous amount of baking soda and salt on the bottom so that the foil was almost covered. I placed the bowl on the mixture on top of the foil - then poured the boiling water/vineagar mixture onto the baking soda mixture - you have an immediate reaction between the metals that produces a bit of sulfa (that stinks but isn't harmful) and cleans the tarnish from your silver.
Now if your silver is stubborn or has been tarnished for years, or if it is a silver plate….this may not work perfectly - and you may need to repeat the process or use additional measures to get it clean. I used an old toothbrush and plain white toothpaste (as it is just a baking soda base) to get in between the flowers and stubborn bits. For my bowl I liked the lived in patina that age had given it so I only left it in for a little as I wanted to retain some of the unique coloring. But the longer you do it the silver can come out looking completely new.
I tried this on several things - silver baby spoons, bowls and silver rings and necklaces. My mom had a silver ring from when she was sixteen that we cleaned, it was practically black with tarnish, It came out looking new!! Forty years later! I was shocked. Remember to only use pure silver jewelry - no enamel or stones as they can be ruined by the mixture.