Mother-of-pearl is found on the shells of mollusks, such as mussels and oysters, and the shells of pseudopods, such as snails. When the young of these creatures come into the world, they create a shell “house” in order to preserve their existence. The walls of this housing are formed with layers their of secretions, ensuring a simultaneous growth of house and creature together.

Depending on the type of animal and the environment in which it lives, secretions create various shapes and colors found on the different types of mother-of-pearl. “White” mother-of-pearl comes from pearl-bearing oysters. It features high reflective properties and is one of the most commonly used types of this material. “ Iridescent” mother-of-pearl is a type in which the colors of pink and green are predominant, while “variegated” mother-of-pearl is a multicolored type. “Stone” mother-of-pearl is white with a low reflective power, while “mat” mother-of-pearl is dull grey and also has a low reflective power.

The shiny quality of mother-of-pearl has attracted attention for thousands of years. The Louvre Museum features mother-of-pearl objects that belonged to the Sumerians and were found in Mesopotamia. In China, a dish with geometric-shaped pieces of mother-of-pearl was found that belonged to the Tang Dynasty in 618-906 A.D. Mother-of-pearl work was also common in ancient Italy, Greece and Cyprus. Today, different types of mother-of-pearl are commonly used in the art world. This type of art is certainly a challenge, for in order for them to be made into works of art, the mother-of-pearl pieces must be thick enough to withstand being worked upon and be of high enough quality to beautifully reflect colors of the rainbow.

Earring Back Types

Butterfly Back: A double looped piece resembling a butterfly that fits over a post. Variations on this design are called push back clasps. The basic post and butterfly back are usually used for stud earrings and lighter weight drop earrings.

Hinged Snap Backs: This clasp features a hinged post that snaps into a groove on the back of the earring. It is commonly found on hoops. Sometimes the hinged post is curved to provide more room to fit around the ear, sometimes called a saddleback.

Hook Backs: This earring backing is simply a long, bent post that fits through the piercing. Hooks have several variations, most notably the shepherd's hook and the French hook. While thin wire hooks reduce the weight of long earrings, making them more comfortable, they aren't as secure as other clasp styles.

Lever Back: A hinged lever snaps shut against the curved post to form a closed loop around the ear lobe. This clasp is very secure and good for large or medium sized styles that drop just below the ear.

Omega: Also called French clips, this clasp has a straight post and a looped lever. The hinged lever closes around the post and is held against the ear with pressure. The omega clasp is the most secure clasp, especially for the larger, heavier earrings.

Screw back: This backing is a slight variation of the standard post and butterfly nut back. Instead of pushing on the back, the nut twists onto the threaded post. A screw back post design is often preferred for expensive diamond stud earrings that require increased security.