Glossary – O
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
-
Old English Font
-
Omega Chain
Small individual metal plates are aligned next to each other and crimped around a mesh infrastructure. Traditional styling is flat in profile with variations in rounded, graduated and reversible styles. Available in numerous millimeter sizes.
-
Omega Clip Back
A method of fastening earrings in which the post is inserted through the lobe and fastened with a hinged clip. Similar to the lever back method except the lever ends in an “O” shape through which the post extends.
-
One Piece Construction
Made from a single casting.
-
Onyx
A semi-precious stone composed of chalcedony (a variety of quartz) found naturally in white or gray. The white variety is generally dyed black for onyx.
-
Opal (October Birthstone)
The birthstone for October. A non-crystalline, rainbow-like mineral consisting of silicon and oxygen.
-
Open Back Rings
Often allow the stone or mounting to be viewed from the inside of the ring and contain less metal than solid back rings.
-
Opera
An industry standard length of a pearl necklace between 28 to 32 inches in length.
-
Optic Character
When a beam of light enters a gemstone, the structure of the gemstone will determine if the light will continue passing in a single beam, or whether the beam will split. Gemstones where the beam of light does not split are called “singly refractive” or “SR”. Those gemstones that split light beams are known as “doubly refractive” or “DR”. Doubly refractive gemstones have two Refractive Indexes; one for each split beam of light. When a gemstone is doubly refractive, the difference in the refractive indexes of the gemstone is called the Birefringence.
-
Oxidized
The interaction between oxygen molecules and other substances causing silver to tarnish or iron to rust.