The following pictures show the marks used by WMF on metalware (pics A through E and 1 to 7) and galss and ceramics from the 1880's to the present:
(A): WMF impressed mark from 1880- ca. 1925; (B) together with (BB) impressed on cutlery/hollow ware from ca. 1880 - 1903; (C) mark on printed material, like catalogues and on jewellery before 1914 together with silver assay stamp "8oo".
((D) from 1909 on; (E) from June 1910 usually a very small mark; (1) from 1907 on printed material; (2) from 1907 on Orivit items together with Orivit design nrs.; (3) on items originally designed by Orivit
(4) 1925 - 1935, after 1935 the upper "bow" is without lines; (5) from 1965; (6) 1938 - 1948 on silverplated ironware with copper or brass layer; (7) 1939 - 1945 on silverplated zinc items.
Also there was from around 1925 to the 1950's a significant production of art-glass (Myra and Ikora) and art-pottery, the last only produced from 1935 - 1949. There the following marks can be found imprinted, engraved or as sticker:
Source: WMF. Glas-Keramik-Metall 1925-1950 (Exhibition catalogue)
(c) G|nter Staffa 1998-2001