Jewelry Term Definitions – Alphabetical O’s
Obsidian - Volcanic glass that is usually black. Obsidian is formed when cools rapidly. Most obsidian is 70 percent silica. Obsidian has a hardness of 5 on the Mohs scale.
Onyx - A variety of chalcedony quartz. Black onyx may be opaque or translucenet and although it does occur naturally in black, it is usually dyed to darken its color. It has a hardness of between 6.5- 7 on the Mohs scale.
Opal - Semi-precious stones that are luminous and iridescent, frequently with inclusions of many colors. Opal is a mineral form of silica, with some water of hydration, found in many varieties and colors, including a form that is milky white.
Opalescence - Milky blue form of iridescence.
Opera Length - This term refers to a long necklace that is usually 24 to 36 inches in length. The term was coined as women flocked to the opera in long strands of pearls. Today the term can be used with any type of necklace.
Oriental Pearl - A natural pearl.
Overlay - A decorative technique which involves two separate pieces of metal. Each piece, which is usually hammered flat, receives different treatments to produce the look. The top piece is sculpted or cut into a specific design and the bottom piece is darkened.
Oxidation - the process where a metal (often silver) blackens or tarnishes as a reaction to oxygen and sulphur.
Category: Jewelry Terms Glossary
About the Author (Author Profile)
Wanda Fitzgerald is a Florida native and an vintage charm collector who loves to share her adventures in an e-commerce jewelry business with anyone who is interested.Subscribe
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Love it! You could do a whole charm dictionary. It would be awesome! The more I read your stuff, the more interesting charms become…