Hi Theo
nice to hear from you!
We could make a try with Johannes II. Giezendanner (1728-1799)
The makers mark could be a IG, as in the catalog picture, but not 100%. And the L for Lichtensteig looks different. The pattern below the L on my spoon confuses me. But it could be something which was overstruck by the L.
What do you think?
Regards, Jörg
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Scan from "Weltliches Silber 2, from the Swiss National Museum"
(I forgot in my original information, yes, the spoon was part of a large pile of Swiss silver, but also some German spoons were included)