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 the pen pictured here to be made beween between 1947-52.
The pen pictured above was made in Germany for the German market and maybe some export. But, there was another more unique version of the 333 1/2, a less common version, that was either made in Denmark or produced for Denmark. See pictures below. The colour is deep and mesmerizing! But, the quality of the celluloid is a bit different. I noticed that the celluloid seems to have been 'folded' and joined as we see in cheaper vintage MB variants and other brands too. When these pens age they tend to pull away and crack at the seams. But, the colour is truly beautiful! Also, the Danish design has a very distinct and interesting short cap top in ebonite or hard rubber. These pens were made between 1941-49, as per the book "Montblanc in Denmark".
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