To prevent the color-change and discoloration they need to be moisturized a couple of times of year with baby or mineral oil. Just apply the oil with your finger or soft-cotton swab and let it sit overnight.
In the morning, wipe any remaining oil from the cameo with a soft fabric cloth--DO NOT use a paper towel.
DO NOT wash the excess oil off or the moisturizing effect of the oil will be washed away also. Moisturize or rehydrate your cameos twice or year and each time after cleaning them. To clean your shell and coral cameos, use a jewelry cleaner that is safe for cleaning pearls.
Many jewelry cleaning solutions available have harsh chemicals in them that are unsafe for pearls, shell cameos and coral cameo-jewelry. If a jewelry cleaning solution says to not clean pearls with it, do not use it on your cameos.
For care-of-cameos, use only those cleaners that state specifically they are safe forpearls.
Pearls, shell cameos and coral cameos all calcium carbonate and must be cleaned gently. A soft toothbrush may be used gently to scrub the cameo.
Follow the pearl-cleaner manufacturer's directions. Do not leave your cameo in the cleaner for longer than thirty seconds.
If you are uncertain about cleaning your cameo jewelry, take it to a professional jeweler for cleaning.
Follow any cleaning of your cameo with a moisturizer of baby or mineral oil. Care-of-cameos includes properly storing it when you are not wearing it.
Again, like pearls, cameos can be scratched or chipped when stored with other jewelry.
Cameo jewelry should be stored individually--not in a jewelry box with other jewelry pieces. It is best if you store your cameo in a fabric jewelry-pouch to protect it from being scratched and chipped.
Given proper care, a cameo can last many generations and become a treasured family heirloom.