Dating gold hallmarks
The testing (assay) and hallmarking of gold and silver items in Britain goes back to the year 1300.
At first the wardens of the Goldsmiths' company would visit guild members workshops and stamp their work with the mark of the leopard's head.
Precious metal (gold and silver, and more recently platinum) objects have by law been tested and marked in England since at least the year 1300, and since 1478 had to be taken to Goldsmiths' Hall in London, from which the term ‘hallmarking’ originate.
There are brief descriptions of different types of hallmarks that you are likely to find in a watch case, and then for the British and Swiss hallmarks there are links to take you to pages of more detailed information.
If you want to get a book about British hallmarking, Bradbury's Book of Hallmarks published by the Sheffield Assay Office is a long established reference.
Pinpointing maker and metal content is often pretty easy. Although reputable firms mark their jewelry, registering marks is not required.
Many of the world’s major jewelry- and watch-making centers require that makers register their marks so they can be tracked. A maker’s mark is a personal trademark for the individual responsible for the precious metal content of the piece. sold at Christie's London in 2012 for ,602, with the help of their marks - a brooch signed Paloma Picasso, Tiffany & Co., with maker's mark T&Co., and heart pendant and chain signed Tiffany & Co. London hallmarks date the brooch to 1994, the rest to 1989. As a result, there is nowhere to research the identity of a signature or mark.