Blue and Red Opal Ring with Diamonds in Gold

• Brilliant Cut - In their naturally occuring state diamonds have little life or sparkle and for many centuries were simply cut in half and worn in amulets. Invented at the end of the 17th century by a Venetian diamond cutter, a "brilliant cut" diamond has 58 facets arranged in a regular geometric relationship, with 33 above the crown and 25 below on the pavilion.
  
  The introduction of the brilliant cut increased the popularity of diamonds in jewellery as it was the first cut to reveal the fire of the diamond, with the light being internally reflected from one facet to another, and was superior to the previously used table cut and rose cut.Variants to the brilliant cut have emerged since the end of the 17th century, but the popularity of the original brilliant cut has continued to the present time, where it is still the most commonly found cut.
  
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• Doublet and Triplet - A doublet and a triplet are both composite imitation stones, consisting of two or three joined layers. A triplet is made with the crown and base of genuine material, but with a centre layer, usually of glass, the object being to make the stone appear larger than it really is. A doublet consists of only two layers.
  
  Opal doublets are quite common and consist of a thin layer of opal cemented to an opal matrix or black glass.

This item has been included into following indexes:

• rings, diamond - diamond and opal 352
• rings, various gems / stones - opal 811