Hi John, your mark:
WAS no entries. Difficult one. Could it read
W.S in an oval shield? Without town mark difficult to attribute.
For example
W.S for Willem Scholten, registered in Deventer 1776-1809
Your mark could it read
SVM conjoined. If so it could be for Pieter Staats van Mecklenburg, registered in Amsterdam 1779-1811
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Source;
Amsterdamse Zilversmeden en hun merken K.A. Citroen;
SVM conjoined for; Pieter Staats van Mecklenburg, registered in Amsterdam, 1779-1811(died), work small silver tableware. 1795-1815 Turbulent time period, today called The Netherlands occupied by French troops and under French law. Introduction of various new (hall)marks, hence the absent of any hallmarks.
http://www.historyworld.net/wrldhis/Pla ... raphID=mis
I go for Pieter.
Peter.