Write an article based on this summary:

Wipe the stone with a soft cloth. Add a little water to the cloth if the stone is very cloudy. Clean the edges of the stone with a soft-bristled brush. Protect your onyx jewelry from water. Wrap your onyx jewelry in cloth when storing it.

Article:
Many common jewelry cleaners, such as ammonia, can be harmful to onyx. The safest way to clean your onyx jewelry is with a clean, dry cloth. A microfiber cloth or other fine, soft cloth is ideal. If wiping the jewelry down with a dry cloth does not remove all the cloudiness or grime, use a cloth that is slightly damp. Blot the stone dry after you clean it. A clean, dry toothbrush or other soft brush can be a great tool for cleaning the hard-to-reach places of your onyx jewelry. Use the brush to remove dirt and grime from the edges of the stone where it meets the metal findings. If the dirt is particularly hard to remove, you can use a slightly damp brush, but be sure to blot the stone dry afterwards. Never soak your onyx, as the water can soak into the porous surface of the stone and alter its appearance. Be careful when washing your hands, and blot the stone dry with a clean cloth if it becomes wet. Never wear onyx jewelry when swimming, bathing, or using household cleaners that may damage the stone. This will keep it from being scratched by other jewelry, particularly during travel. Velvet and cotton are ideal, or you can purchase a jewelry pouch to store each onyx item in.