No. 333 1/2
The 333½ was produced before, during, and a little after WWII. The pens during the war were made with steel nibs, but the ones before and after the war were made with 14c gold as we see in this picture. The 333 1/2 was armed with a Kontolfüller or simple piston filler.
This model was more commonly found in black. However, one catalogue from the 1930s does confirm that the 333 1/2 came in black, blue, green, and pearl. Today, the coloured versions are far rarer and command a much higher value. Collectible Stars I rates the blue marbled 333 1/2 as a 10 on a 12-point scale, which the author considers a "once in a blue moon" find.
Catalogues from the late 1930s show the 333 1/2 but with one cap ring. On the other hand, a catalogue from the late 1940s shows a black 333 1/2 with two cap rings like mine. Also, Collectible Stars I shows two variants of blind caps, and the one that looks like my pen is said to be a post-war version. So, I date my pen between 1947-52.
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