Maker: Osmia.
I have, I’m afraid, very little to offer beyond the mere dimensions of this pen, as my reference materials for Osmia are extremely limited. What little I have suggests that a steel-pointed model must almost certainly be a post-war item; before the war, Osmia was an appendage of Degussa, whose reason for existence was the selling of precious metals, and during the war steel was generally being applied to more bellicose pursuits. I don’t think it is from very long after the war, however, as the piston seal is of cork and that material was pretty quickly superceded by synthetics in this role. Update: After the initial writing of this page, I discovered that the Nazi regime put more restrictions on the use of gold than of steel during the war; as far as point material goes, steel might well prove that this is a wartime pen. Further update: This shape of pen is known to appear with increasing degrees of Faber-Castell branding into the 1950s, but that does not settle the incept date.
As an ambassador for its maker, this pen does a pretty good job. The mechanism functions well, and the point has a pleasant degree of give to it; I would happily call it semi-flexible. I can understand why those who have them so infrequently part with them.
Production Run: As a pure guess, probably c.1940 to c.1955. I will happily change this if anyone can provide solid data. Update: an ad with a somewhat provisional date of 1945 shows this general style of pen selling for DM 6.- to DM 19.50. The use of DM rather than RM guarantees it is a post-war ad, but there is no guarantee that this specific model was included in it’s message. Update More: I got a note from fountainpen.it pointing out a French ad from 1937. The 64 shown there is a somewhat more streamlined object than the example I handled (and closer in appearance to my Faber-Castel 664). If this were a Parker, I wouldn’t hesitate to say the blockier object is even older, but my correspondent points out that the lack of bands suggests production during WWII. Hard data is still solicited.
Cost When New: Assuming that ad to have meant this pen, we may assume further that it was at the DM 6.- end of the price range. Postwar exchange is a vexed topic, as the Mark was artificially devalued for a long time after the war; from an outside perspective, this was the equivalent of about $1.40, but that would only have been a bargain to a tourist (for modern value, try this calculator, but keep in mind that the answer is inaccurate relative to the amount of bread DM 6.- would have bought a German citizen).
Size: 12.3 cm long capped, 15.0 cm posted, 11.4 cm uncapped.
Point: Steel.
Body: Celluloid.
Filler: Piston , capacity approx. 1.0 ml
Osmia 64; note that it never actually had cap bands, just decoration indicative of them.
I include a picture with the cap on because it shows both the model indicator and the German tendency of the time to have pens much more compact when capped than open.
If you are relying on the preceding information to win a bet or impress a teacher, you should read the site’s scholarly caveat. Remember, this is the internet, and it’s full of bad information.