I found this article about caring for fine jewelry and I mostly agree except about not using ammonia. Mr. Clean, water, and a small amount of ammonia is used every day by local jewelers to clean jewelry and it works amazingly. This mixture is equal to jewelry cleaner and is used instead of jewelry cleaner. This article also points out that using toothpaste is a bad idea and I do agree with this one. using toothpaste to clean your jewelry is definitely an old wives tale. I’ve seen youtube videos where this is done with really cheap jewelry and it does make it shinier, but I would not use it on my fine jewelry. This article also talks about storing jewelry and gives a few other tips.
Some types of jewelry require especially delicate cleaning methods. Strands of pearls, for example, should not be submerged in liquid because doing so can cause the silk cord the pearls are strung on to rot. Instead, they should be wiped down with a damp cloth, Batisch said.