I have a silver piece with the stamp of "M & K" , "900" and, in addition, a faded stamp that reads "HNA" or "ØHNA" - but the first and last letters are missing.
M & K could be Mayerhofer & Klinkosch of Vienna?
I don't see the Vienna city mark of Diana indicating 900/1000 - would they have used this "900" instead perhaps for an export market? Or is there another maker that used M&K?
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