It's a jeton, probably by Lauer from the early 1820's. Here's a link to a similar one dating 1814; I'm pretty sure Nicolaus is the Grand Duke at that period. As such it could date from 1814 but I don't recall seeing the Duke listed in my references that early.
Edited to add: probably worth $5-15 US depending on who might want it. These jetons were produced by the ton so lots of them survive.
To me, it looks a bit crude for Lauer, but it does appear to be a German-executed jeton. It seems to commemorate Czar Nicholas I (reigned 1825-55) ["Nicolaus v. Russland"]. He encouraged many Germans (especially those being persecuted in Poland by the Poles) to emigrate to Russia; these immigrants were generall known as the "Volga Germans."
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Edited to add: probably worth $5-15 US depending on who might want it. These jetons were produced by the ton so lots of them survive.
You want how much?!!
NapoleonicMedals.org
(Last update 3/6/2007)
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