These assay offices were established by law, superseding the medieval Guild system of regulation.
These hallmarks were used for plate, vessels and candlesticks etc.
In Switzerland in the 1920s a system of responsibility marks for precious metal watch cases was introduced.
These are called Poinçons de Maître, which translates literally as "Master's Punches" but are usually called "Collective Responsibility Marks".
• And Many More Standards for precious metals in Switzerland originated in Geneva in the 15th century, the first recorded regulation concerning the fineness and marking of silver was enacted by Bishop John of Brogny in the year 1424.
This led to some confusion during the Brexit referendum about what was meant by control of/at the borders.
These can be used to identify the maker of a precious metal watch case.
There is a full description of this system and tables of the marks at Poinçons de Maître: Case Maker's Marks. The Swiss Precious Metals Control Act of 23 December 1880 introduced a uniform system of hallmarking for watch cases to be used throughout Switzerland with the marks shown in the picture here.
Although the Swiss Precious Metals Control Act of 1880 defined standards for gold and silver watch cases, the British Merchandise Marks Act of 1887 caused several changes in Swiss hallmarking, in particular the two Swiss standards for silver were not accepted in Britain, and the British also inadvertently caused the Swiss to create their own national brand or trade mark "Swiss made".
Swiss hallmarking before 1880 and after 1933 is rather outside the scope of this page, but I mention some of the changes made in 1933.