During the 1920s and 30s Platignum produced a wide range of models. By the end of that period they were turning out pens and sets in very colourful – even gaudy – plastics. Many of these pens were beautiful and probably pleasant to use but often they suffered from quality issues that affected their durability. In particular the steel or plated nibs were subject to corrosion.
I would place this blue pen in the 1920s, with its flat top and straight sides. I think we are entitled to call this pattern Lapis Lazuli. It’s certainly quite close to the appearance of the mineral.
These “Seniors” appear to have been better made than some other Platignum models of the time as quite a few have survived in good condition. The plated nib is interesting. Imprinted on it are “Platignum” followed by a plain “M” that might mean medium, then another “M”, this time larger and in a circle, doubtless referring to Mentmore, the parent company. This is quite a noticeable nib and it would be useful if a date could be assigned to it. Is this the original nib (unlikely) or a later, but appropriate, replacement?
A few years ago I would have taken little or no notice of an old Platignum. I certainly wouldn’t have bought one and when one turned up in a batch I’m afraid that it went into the trash-bucket. I was wrong. These pens are just as much part of the history of the fountain pen as the finest Onoto or Swan.
It appears that, like other manufacturers, Platignum re-used names for different models. There is a later, streamlined Platignum Senior in the post-war period.
Thanks to Paul S for photos and information.