Silver is one of the most versatile of natural metals, and its extreme malleability has enabled silversmiths to create a wide variety of wares, both beautiful and functional. Initially silver was primarily appreciated for its bullion value, representing the coinage of the realm. Goods were often pawned or melted down, and many splendid pieces were "recycled."

Many attempts were made over the centuries to control the silver standard but perhaps the most successful "quality control" system evolved as early as 1327 when King Edward I of England decreed that every item made from silver would be "hallmarked" to ensure purity.

A crowned leopard’s head was stamped on goods to indicate each piece had been tested and met the sterling standard.  By 1544 a new hallmark was introduced that superseded the Leopard's head as the mark of purity. The Leopard's head then became the city mark for the London assay office, and other marks were introduced to represent other cities (assay offices) around the country.
A mark indicating the purity of silver was also introduced, the Lion Passant, which showed a Lion facing left. This mark indicated a silver content of at least 92.5% and became known as the Sterling Standard.
To identify the date of production of a piece of silver, alphabet letters were struck in various shield-like forms on the silver.  But the alphabet system re-set every seventeen years so it takes patience and a library to identify the year of making.  

The hallmark system was continuously refined and many monarch’s contributed their own “touch” to the system.   A Duty Mark was introduced during the years 1784 – 1890 as an indication that a duty or tax had been paid on the object.
The Master Craftsman was responsible for the quality of the work that left his atelier or workshop, regardless of who made the item. Hence the responsibility mark is still known today in French as le poinçon de maîtreliterally "the maker's punch," often referred to as “maker’s mark.” A penalty of 10 years imprisonment still exists if convictedfor the mis-use of English hallmarks.  

Hallmarks or makers’ marks that are so worn by use or by over-polishing will cast doubt on the condition of the article and lessen its overall value. The value of even the finest piece of antique silver will be diminished if the article has been damaged or abused, while well-cared for articles will retain their value.1

See our section Cleaning Silver for tips.

1 Derbyshire, Lydia, Antique Silver, The New Compact Study Guide and Identifier, London, 1994, p. 11.