Simple mark "Sterling Handle" on lower spine. Engraving reserve only on one side, and name "Dietz" is read with blade facing up and away. Blade reads Mirrorstele, not Mirror Steel. Bad, hasty photo but front design includes hanging fruits. Could it be a German or continental commercial useage (Hotel, gasthaus, etc.), or perhaps an export?
The trade mark 'Mirrorstele', if I understand it correctly, was registered by Reed & Barton on the 30th November 1926, to be used on: 'CUTLERY MADE WHOLLY OR PARTIALLY OF BASE METAL-NAMELY, TABLE KNIVES, TABLE FORKS, AND TABLE SERVING PIECES'
Noticed this phenomenon on a few knives, the handle is not marked with company name; sometimes the handle is only marked "STERLING" +++ Once I had a set of Tiffany knives which were marked on the blade only; the handles had no marks whatsoever which made me suspicious +++ I really am not sure why this happens, but I pay close attention to knifes because every once in awhile the handles are not fully marked +++