The use of hallmarks on jewelry and objects made from precious metal began in the 1400’s, however many unmarked pieces exist.
The passage of time and repair work has marred or eliminated marks from many pieces making them harder to identify the precious metal content, the country of manufacturer or the maker.
In 1910, the Dog’s Head mark replaces the eagle mark on earlier French platinum pieces and French pieces may have a maker’s mark.
Hallmarking systems are developed and implemented in Austro-Hungary, Russia, Sweden, and Finland in the 19th century.
Similar to the Sheffield plate process, it involves the lamination of a sheet of gold to a sheet of base metal.
Gold filled is a variation of this process and both are normally marked.
This required that a manufacturer put a quality stamp on his karat gold or silver items along with their hallmark. During the process of sizing a ring, replacing a chain or from normal wear, marks can disappear.