An antique cameo should have a “c-clasp,” which means the brooch pin loops under a crescent shaped piece of metal to hold it in place. Since authentic cameos are set in gold or silver, you should always check the setting for a hallmark that indicates the kind of precious metal used (14K, 925, 999, etc.).
How can you tell the age of a cameo?
Look at the hinge or pin on the back. If the pin on the back is a plain c-clasp(the brooch pin loops under a c shaped piece of metal with no roll over fitting)– chances are its an old/ antique brooch. Mythology shell cameos usually date from the 18th Century to the very early 20th Century.
Are cameos made of ivory?
Know your materials- authentic carved cameos are made from natural materials, such as shell, agate, onyx, ivory, coral, mother-of-pearl, and various gemstones. Authentic painted cameos are typically made from porcelain. If the cameo in question is made from plastic or resin it is a fake.