The meaning of silver hallmarks with crowns differs from country to country. Identifying them can give you clues to determine where it was made, who the maker is, and even if it might have a higher value than other items similar to it. Armed with a little knowledge, and a reference guide on silver hallmarks, you will be able understand a little history of your own silver, and recognise a valuable treasure when you see one.
Learn to recognise British sterling hallmarks. Four to five marks, stamped into the silver, will all have the same shape, called a shield or cartouche. Within these shields are the maker's initials, town marks, the sterling guarantee and a date mark. A crown over the maker's initials means that the monarchy has chosen that silversmith to produce items for them, thus the title, "Crown Jeweler." Town marks sometimes have crowns. Most notable are the marks for Sheffield, which is a crown, and for London, which is a leopard head sometimes wearing a crown. Irish silver bears a sterling mark of a crowned harp, instead of the English walking lion. Irish silver and silver made by a "Crown Jeweler" are rarer, and have more value than other similar silver.
Look for crowns in a heart-shaped cartouche. The national marks of both Finland and Sweden bear this unusual mark. The Finnish mark has a single crown in the heart. Sweden uses three crowns. Hallmarks can be very small, so a magnifying glass is an invaluable tool for finding and reading them.
Familiarise yourself with American silver hallmarks by studying reference books and hallmark guides. Some American marks are very straight forward, with the name or initials of the maker clearly marked. Others are very cryptic, using symbols with no particular meaning. Crowns in American silver hallmarks, are simply a part of the logo that the American silversmith wanted associated with their wares. A crown in the hallmark may suggest quality to the buyer, but it is not a sign that any standard has been met. The word "sterling" or ".925" denote American sterling standards, not crowns.
Take a magnifying glass with you whenever you shop for antique silver. Most silver hallmarks are very small and impossible to read without one.