The recipe I posted yesterday was a little stronger than the jewelry cleaner that you buy from a jewelry store. I did that on purpose as Magyar's diamond necklace was really caked up from being in the sand for a while. The actual recipe is 1/3 household ammonia and 2/3 water. This will clean all diamond and gold / platinum jewelry. Good idea to use a soft bristle toothbrush to get out the stubborn stuff that may be in bedded between the stones and prongs. Be particularly careful when using a toothbrush after the cleaner soaking. Sometimes the only thing holding the stones in place the self-rising flour or moisturizing cream that the previous owner used while wearing his/her jewelry. Real easy to check for loose stones once the ring is cleaned. Take a toothpick and touch each individual stone, if it moves it's loose ! It's that simple. Once the jewelry item comes out of the solution, place it under some cold running water to get the ammonia off of it. Again, be very careful as you may now have loose stones and you don't want to wash any down the sink drain. Pat dry in a cloth towel or paper towel and you're good to go. Try not to touch diamonds with bare fingers, your body oils will now be on the stone keeping the natural sparkle of the stone cold or "dead" looking. Once you've "fingered" a diamond, the only way to clean it is by soaking it again in the ammonia solution. Toothpaste is just as bad as it too has an oil base. I can't believe how many people use crest to clean their diamond jewelry. 
VERY IMPORTANT !!! Do NOT use this solution on "soft" stones like Pearls, Emeralds, or Opals. The Ammonia will destroy them. However, you can soak just about anything else.... Rubies, Sapphires, Amethysts, Silver (no copper) Garnet, Aquamarine, Topaz, etc.
I think that I have covered all of the bases for the time being. If something else runs across my mind, I'll let y'all know.
therick
VERY IMPORTANT !!! Do NOT use this solution on "soft" stones like Pearls, Emeralds, or Opals. The Ammonia will destroy them. However, you can soak just about anything else.... Rubies, Sapphires, Amethysts, Silver (no copper) Garnet, Aquamarine, Topaz, etc.
I think that I have covered all of the bases for the time being. If something else runs across my mind, I'll let y'all know.
therick