Re: Jordan Surname from Czarnikau, Posen, Prussia
The location Czarnikau in Province of Posen (Prussia) is nowadays Czarnkow in woiwodship wielkopolskie in Poland. You didn't mention the confession of the family. The Catholic registers (from 1699 to 1913) in Polish and German language are available on films (https://www.familysearch.org/search/catalog/71854; https://www.familysearch.org/search/catalog/834201), also the Lutheran registers (1781-1877) in German language: https://www.familysearch.org/search/catalog/385001.
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