Maker: Faber-Castell (in the case of my example).
As Faber-Castell took over Osmia`s operations to an increasing degree, they applied more of their branding to the fountain pens Osmia produced. The 66X had appeared in full Osmia livery in an more squared-off version, shaped rather like the 64 but carrying a gold point, and one sees what we might call transitional models with Faber-Castell printed on the caps and Osmia on the barrel in both the earlier shape and the more streamlined profile of this example. The late expression of the form finds no mention of Osmia, but the logo continues to appear on both the cap jewel and the imprint on the point. The exact dating of these various incarnations is a little tricky, the streamlining coming about in the mid-1950s and the suppression of the Osmia name about 1960.
The X in the model number reflects possible variation in the point size of these pens. The final digit may be from 1 through 4, in order of ascending size. The point size is usually stamped in the Osmia logo. The size of the point informs the size of the pen, so there are four distinct sizes to this pen; like Parker UK’s Duofolds, the scale is very consistent, so telling one from another without checking the impression or reference to a ruler can be tricky. An oddity about this pen: the point and feed unscrew, but the line width is indicated in the barrel impression.
These pens frequently have flexible points, but not always. The performance tends to be quite good, flex or not, although some find that the feeds are a little more given than the average pen’s to letting ink go when given a bump.
Production Run: c. 1945 to c. 1965; these dates are highly speculative, and not to be quoted with any assurance.
Cost When New: An ad provisionally dated to 1945 shows Faber-Castell/Osmia pens selling from DM 6.- to DM 19.50, so… somewhere in that range, probably. As the conversion of Marks to Dollars for the entire (speculated) run of this pen is a little tricky, and since I don’t actually know where in that range this model falls, I’m not going to suggest equivalent dollar pricing.
Size: 664 streamlined version– 12.8 cm long capped, 14.1 cm posted, 11.8 cm uncapped.
Body: Celluoid until at least the appearance of the streamlined shape, but the clarity of window and lack of smell in my example indicate a more modern plastic took over at some point in the production.
Filler: Piston, capacity of 664 approx. 1.5 ml. This is huge compared to the similarly-sized Pelikan 140, and leads me to suspect a two-stage telescoping piston of the sort Montblanc was using at the time. Research continues (which is to say I don’t want to actually take mine apart without a better reason than satisfying curiosity).
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