Hi Theoderich,
It is a Dutch tea spoon made in Leiden hence the key mark with year letter script letter L for 1794 or script P for 1797, for 2nd standard or
"kleine keur" first mentioned in 1661. The year letter could be above, next and under the key.
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The maker's mark reads
GHN for: Gerardus Hendrikus Nieuwenhuyzen registered in Leiden from 1792-1818. He used
GHN from 1792-1811 and
N above a Poppy in a lozenge (French style) from 1812/1818. Gerardus Hendricus Nieuwenhuijzen died in Leiden February 3, in 1818, born in Leiden, 49 years old, residing in Mare wijk 6 nr 1199,
zilversmid by profession.
See Leiden:
http://www.925-1000.com/forum/viewtopic.php?f=5&t=32028
Best wishes,
Peter