1840 English Amethyst Watch Key Fob in Rolled Gold

• 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.
• Rolled Gold - A type of gold plating devloped in the early 19th century, similar to Sheffield plating of silver, where the the gold is fused under pressure and heat to a base metal, usually brass, and then rolled into sheets of the required thickness.
  
  The thickness of the gold plate can vary. In Britain the thickness of the gold is measured in microns. A micron is one-thousandth of a millimetre and 20 microns of gold is considered good quality. In the USA a differnt method is used that takes account of the total weight of the object.
  
  Also, the purity of the gold, measured in carats can vary, with 24 carat being the purest. The gold in most rolled gold objects will be between 9 and 14 carats.
  
  There are other chemical and electroplating methods of applying gold plate to a base metal, but rolled gold is considered a superior plate to a "gold plated" object.
  
  Depending on the country and date of manufacture, the object may be stamped "Rolled Gold" or similar, but if there is any doubt as to whether an object is solid gold, or some type of gold plating, it is preferable to have it tested by a jeweller.

This item has been included into following indexes:

• designer key rings and key fobs - jewellery 64
• watch keys (singles) - jewellery 62