Levy & Son Agate Double Bar Brooch

• Agate - Agate is a type of semi-precious gemstone that is made up of silica dioxide, a mineral that is also found in quartz. It is known for its distinctive banded patterns, which are created as layers of silica are deposited in different colours including red, orange, yellow, green, blue, and purple. It is often used in jewellery, decorative objects, and other decorative items, and it is prized for its beauty and durability. Agate is found in many parts of the world, including Brazil, India, and the United States.
• Gilding - Gilding is a method of ornamentation whereby a thin sheet of gold metal is applied to items made of wood, leather, ceramics, glass and silver for decorative purposes.
  
  For furniture including mirrors, the sheet of gold is usually applied over a coating of gesso. Gesso is a mixture of plaster of Paris and gypsum mixed with water and then applied to the carved wooden frames of mirrors and picture frames as a base for applying the gold leaf. After numerous coats of gesso have been applied, allowed to dry and then sanded a coat of "bole", a usually red coloured mixture of clay and glue is brushed on and allowed to dry, after which the gold leaf is applied. Over time parts of the gilding will rub off so the base colour can be seen. In water gilding, this was generally a blue colour, while in oil gilding, the under layer was often yellow. In Victorian times, gilders frequently used red as a pigment beneath the gold leaf.
  
  Metal was often gilded by a process known as fire gilding. Gold mixed with mercury was applied and heated, causing the mercury to evaporate, the long-term effect of which was to kill or disable the craftsman or woman from mercury poisoning. The pursuit of beauty has claimed many victims, not the least of which were the artists who made those pieces so highly sought after today.

This item has been included into following indexes:

• brooches, bar brooches - bar brooches, other 777
• brooches, depicting - bouquet of flowers 100
• brooches, period or age - New Zealand Colonial and later 87
• brooches, set with - agate 236