Hallmarks are stamps used to indicate the purity and origin of fine metals. Individual countries and companies use different systems of notation that can be used to track the quality, source, and date of your jewelry (and sometimes its maker). A little information can go a long way in helping you find out more about your antique jewelry and its potential value.
What do the marks on my old jewelry mean?
British gold made between 1798 and 1975 is stamped with a crown the karat weight. Until 1854, only 18k and 22k were allowed.
Many pieces carry a 3-digit number that indicates the gold quality in percent, not karats (Read more about gold quality…)
• “999” = 24 karat = 99.9%
• “916” = 22 karat = 91.6%
• “750” = 18 karat = 75%
• “585” = 14 karat = 58.5%
• “417” = 10 karat = 41.7%
In France, commercial gold must be at least 18k. This is certified by the eagle’s head stamp, used on all gold jewelry made after 1838.
Since 1906, precious metal jewelry in American is required to have a purity mark. However, there has never been a standardized system of marking in the United States, so many makers invented their own systems. American makers sometimes imitated British marks, making them hard to distinguish – but if it has a purity mark, karat is spelled with a “k” on American jewelry.
Like gold, pure silver is too soft to be made into jewelry, so it is blended with other metals such as copper. An item that consists of 92.5% silver (or “925”) qualifies as “sterling,” the standard set by various countries to regulate commercial silver. A sterling mark is one of the most common stamps you will see on silver jewelry.
Image: British Silver Hallmarks
a – Maker’s Mark
b – Assay Mark (Early Sheffield)
c – Date Letter
d – The Sterling Mark
e – The Duty Mark (monarch’s head)
British marks indicate four things:
- Purity – the lion passant (“lion walking”) is the symbol for British sterling.
- Assay office – like US coins stamped with the initial of the city where they were minted, British silver often bears a symbol showing where it was graded.
- Date – Every year has a unique code letter. Silver makers re-used the same letters of the alphabet by starting over about every 20 years with a new style of letter stamp.
- A makers mark, a tax mark, or import mark were optional but sometimes appear on antique pieces.
French standard silver (at least 800 fineness) is marked with a boar’s head.
After World War II, Mexican silver makers started a system of notation. Sterling is indicated by the Mexican eagle.
The most common way of marking precious stones in a piece of old jewelry is with its corresponding birthstone symbol, or zodiac sign.