• Old European Cut - a brilliant cut variation pre-dating today's round brilliant diamond.  There is usually 58 facets including a small table and a deep crown and pavilion.

  • Old Mine Cut - a brilliant cut diamond pre-dating the Old European Cut diamond.  It has a cushion shaped girdle profile, a small table facet and a deep crown and pavilion. 

  • Opaque - when light rays cannot penetrate an object.

  • Organic Gem - materials formed from living or once-living organisms.  Examples of this would be amber, pearl, ivory, coral, etc.

  • Overlay - when one sheet of metal is soldered onto another.

  • Overtone - a tint of color that appears on the body color (main color) of a pearl.  An example would be a white pearl that has a tint of pink in it.