French Boulle Mantel Clock with Marti Movement, c.1860

• Ormolu - Ormolu was popular with French craftsmen in the 18th and 19th century for ornamental fittings for furniture, clocks and other decorative items. True ormolu is gilt bronze, that is bronze that has been coated with gold using a mercury amalgam. Due to the health risks associated with using mercury, this method of creating ormolu was discontinued in France in the 1830s. A substitute was developed consisting of about 75% copper and 25% zinc, however it was inferior to the bronze version. It was often lacquered to prevent it tarnishing.
• Tortoiseshell - Tortoiseshell is a translucent material that comes from the horny carapace of a certain types of turtles, including the hawksbill turtle. It is often therefore mounted on a colour underground - often red - or inlaid with gold or silver thread, as seen in Boulle furniture.
  
  The texture and colour nuances of the material are extremely important. Heated tortoiseshell can easily be formed into various shapes. Like other natural materials, tortoiseshell becomes more beautiful with use. In a time before plastic, tortoiseshell was widely used for small objects such as combs and powder compacts.
  
  In 1973, the trade of tortoiseshell worldwide was banned under CITES (The Convention on International Trade in Endangered Species). Prior to importing or exporting items containing tortoiseshell a CITES permit must be obtained. Tortoiseshell items cannot be traded on Ebay.
  
  "Faux tortoiseshell", another case of man initiating nature, is made from old-style plastics such as celluloid and cellulos and is coloured with red, yellow and brown spots to imitate the genuine article. It is commonly used in glasses frames, musical instruments and costume jewellery.
• Movement - The technical name for the workings of a clock or watch, and does not include the dial or case.
• Boulle - Boulle work is the name given to tortoiseshell and metal inlay using brass and sometimes silver, found on furniture and smaller wooden objects. It originated in Italy but was developed by Frenchman Andre Charles Boulle (1642 - 1732) under Louis XIV.
  
  Boulle was appointed Royal Cainet Maker to Louis XIV and designed furniture and clockcases for the monarch.
  
  In preparation, the tortoiseshell and metal were cut together following a design, using a fine fret saw.
  
  In the application of the Boulle, the carcase of piece of furniture was covered with the tortoiseshell which in turn was inlaid with the matched designs in metal, which in turn was elaborately engraved.
  
  The use of Boulle work furniture continued mainly in France until the 19th century.

This item has been included into following indexes:

• clocks, mantle & shelf, material or style - gilt metal / ormolu 536
• clocks, mantle & shelf, period or origin - French 737
• clocks, material or decoration
  • Boulle 94
  • tortoiseshell cased 99