I was recently tasked with fixing a bracelet for my mother in law. While I was looking at the pieces, I realized there were a few numbers marked very small in one area---these numbers meant that the bracelet was some sort of silver. So before fixing the bracelet, I decided to give the pieces a good cleaning as they were quite tarnished. Here's a recipe for homemade silver jewelry cleaner. I don't know if it'll work with other metals, but I definitely wouldn't use it on rocks, gemstones, pearls, etc.
I ended up trying two different recipes because at one point, I was concerned the intricate beads were not getting clean enough. I used recipe 1 first for all of the beads and then recipe 2 for follow up with the dirtier beads.
Step 1: BoM
1/2 cup boiling water
1/4 cup vinegar
3 tsp salt
3 tsp baking soda
1 cup boiling water
1 tbs baking soda
***You can make larger amounts, I only needed to clean the parts of a bracelet so I just made a small amount.
Step 2: Prep
Line a bowl with tin foil and bring water to a boil. Once the bowl is lined, lay your jewelry out on the tin foil (which I forgot to do until I had already poured in the vinegar).
Step 3: Mix
Mix the baking soda and salt with the boiling water. Pour into tin foil lined bowl.
Step 4: Vinegar
Slowly pour the vinegar into the jewelry bowl. Be prepared for some chemical reactions :-)
Step 5: Soak
Let the mixture sit for 15-30 minutes. Some of the pieces cleaned up faster than the more intricate ones, so I removed pieces as they were ready. If you're short on time, you could use a toothbrush or q-tip to scrub the harder to clean pieces.
After the soak with the beads in recipe 1, I boiled more water and put the dirtier beads in recipe 2. This got a lot of the black gunk off. At one point I was worried the intricate beads might not actually be silver, so I took a toothpick and scraped a bit---the tarnish started coming right off. So I let the beads soak in recipe 2 for about 20 minutes.