Bernhard J
·The movement clearly is Swiss made, the so-called "Jürgensen type", produced by several high grad manufacturers. The case does not seem to be Swiss, but American rather. The mark in question is not a continental European mark, see for a list for various eras and places: https://watch-wiki.org/index.php?title=Kontrollstempel.
It looks similar to e.g. this English mark, but misses all other marks, assay office, date letter, etc., so that I would exclude English marking.
It looks similar to e.g. this English mark, but misses all other marks, assay office, date letter, etc., so that I would exclude English marking.
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