Topic summary
Assay mark
Extracted from the Wikipedia article Hallmark.
General overview
Historically, hallmarks were applied by a trusted party: the "guardians of the craft" or, more recently, by an assay office (assay mark). Hallmarks are a guarantee of certain purity or fineness of the metal, as determined by official metal (assay) testing. Hallmarks include information not only about the precious metal and fineness, but the country from which the item was tested and marked. Some hallmarks can reveal even more information, e.g. the assay office, size of the object marked, year the item was hallmarked - referred to as a date mark (also known as date letter).