French Mother of Pearl Opera Glasses with Case

• Mother-Of-Pearl - Mother-of-pearl, technical name "nacre", is the inner layer of a sea shell. The iridescent colours and strength of this material were widely used in the nineteenth century as an inlay in jewellery, furniture, (especially papier mache furniture) and musical instruments.
  
  In the early 1900s it was used to make pearl buttons. Mother-of-pearl is a soft material that is easily cut or engraved.
  
  Nowadays it is a by-product of the oyster, freshwater pearl mussel and abalone industries.
• Guilloche - A form of classical decoration consisting of a repeating ornament of interlacing curved bands, sometimes forming circles, and further decorated with rosettes or other flower forms.
  
  The name is derived from the inventor, French engineer Guillot, who invented a mechanical method of inscribing fine repeating patterns on to metallic surfaces.
  
  On enamelled items with guilloche decoration, the surface is firstly engraved with the repeating pattern, and then covered with several layers of enamel, each of which is fired.
  
  Where the item has not been enamelled the form of decoration is usually called "engine turned".

This item has been included into following indexes:

• opera glasses - optical 165
• spectacles - optical 217