Being able to identify a hallmark flag on a piece of silver is vital to anyone looking to buy or sell silver antiques. Hallmark flags are markings emblazoned onto pieces of silver that can be used to identify the manufacturer, the rough date and sometimes the place it was made. Hallmarks were used extensively in the UK, Germany and France, but in America they weren't as strictly regulated. This can make identifying American silver hallmark flags more difficult, but learning a few basics about hallmark identification can help you spot a bargain that others might miss.
Look for a three digit number on the hallmark. Hallmarks are actually just markers of purity, not actually indicators of place or time of manufacturing. Many manufacturers have included their own "makers marks" on silver products they made. The three-digit number is the true hallmark, the purity indicator. Standard, or "coin" silver will be marked "900," and better quality silver has a larger number. "Sterling" silver is marked by "925," but the word "Sterling" can be substituted in some instances.
Research the original British silver marks (see Resources). The British had a very clear system for hallmarks, and old pieces of silver can generally be dated and even located with a reasonable degree of accuracy. You might have an old British piece of silver, or even an American "pseudomarked" piece. "Pseudomarks" were used in America between 1840 and 1920, and closely resembled the original British markings. British markings generally included a lion emblem, signifying sterling quality, and a different emblem for the city. Sheffield, for example, was shown by a crown logo.
Check the lower side of your piece for a "touchmark." American silver doesn't have a uniformed hallmarking style, so manufacturers generally put an individual mark on the silver, called a "touchmark," which can be checked against lists of known markings (see Resources).
Check for Mexican markings. Mexican silver has a few general hallmarking standards and can be more easily identified than original American pieces. Check for an eagle marking, indicating that the piece might have been made in Mexico from 1940 to 1970, or the words "Sterling" or "Silver," possibly indicating Mexican silver from as far back as 1860.
Learn about different hallmarks used all over the world. An old piece of silver could have originated from many places around the world, so it is import to become familiar with some of the hallmarks used in other parts of the world (see Resources). For example, Spanish silver often has a five sided star hallmark, and Czechoslovakian silver is often marked with a triangle with a number inside.