Geometric Gemstone Brooch from 1930s

• Emeralds - Emeralds have been used in jewellery making for thousands of years, and are prized for their deep green colour, which is caused by the presence of chromium and vanadium in the mineral beryl. Because of their rare colour, emeralds are often more valuable than diamonds of a similar size and quality. In jewellery making, emeralds are typically cut into round or oval shapes to maximize their color and clarity. They are often set in gold or platinum and used as the centrepiece of a piece of jewellery, such as a ring or necklace. They can also be used in combination with other gems, such as diamonds, to create intricate and beautiful designs.
• Openwork in Jewellery - Openwork, also known as pierced work, is a decorative technique used in jewellery making that involves removing or cutting out sections of metal from a piece of jewellery to create a pattern or design. This technique can be used in a wide range of jewellery styles, including necklaces, bracelets, earrings, and rings.
  
  Openwork jewellery can be made using a variety of different techniques, including hand carving, sawing, and laser cutting. The design can be simple or complex, and can feature a range of different shapes and motifs, from delicate floral patterns to bold geometric designs.
  
  One of the advantages of openwork jewellery is that it can add visual interest and depth to a piece without adding a lot of weight or bulk. This can be particularly appealing in larger pieces, such as necklaces and bracelets, where heavy materials can be uncomfortable to wear.
• Circa - A Latin term meaning 'about', often used in the antique trade to give an approximate date for the piece, usually considered to be five years on either side of the circa year. Thus, circa 1900 means the piece was made about 1900, probably between 1895 and 1905. The expression is sometimes abbreviated to c.1900.

This item has been included into following indexes:

• brooches, diamond
  • diamond and emeralds 204
  • diamond and pearl 392
  • diamond and ruby 419
• brooches, set with
  • diamonds 497
  • rubies not gold 92