Undated
BM
The illustrated hallmark is Chester 1909; this is an object's assay date, not the BM mark's full use period.
gold · silver · Chester
Berthold Muller Hanau was largely imported in UK between the end of the 19th and the beginning of the 20th century. Berthold Mueller was an import firm, who distributed a lot of Neresheimer - see John Culme: The Directory of Gold-and Silversmiths, Jewellers and Allied Traders 1838-1914, Vol.1 page, page 335. The firm changed its name 1915 to Berthold Miller and was listed as wholesale silversmiths and jewellers, antique reproduction in , ivories, miniatures, enamels, and so forth. 1909 hallmark