For your more delicate jewelry pieces a soak will clean better without harming the jewelry. Soak the jewelry in a half-and-half solution of cold water and household ammonia for at least thirty minutes. Lift the item out and gently tap around the front and back of the mounting with a small soft paint brush. Swirl the item in the solution to rinse. Finally rinse in warm water and dry with a lint-free cloth like microfiber. Be sure not to snag the prongs holding stones.