No. 146 G
If I could keep only one pen in my entire collection and had to give everything else away, then the 146G would be that one pen! What a wonderfully expressive OB nib it has!
It is unclear as to what the 'G' in the model signifies. Some believe it means 'glatt' or glossy finish. But this theory does not always hold up. Some believe it means 'gold' for gold nibs in post-war pens (because they used steel during the wartime instead). But, this theory does not explain pre-war catalogues that show pens with 'G' in the model.
The celluloid 146 was made between 1949-59. The longer-than-typical ink window and ski slope feed on my pen indicate that it is one of the earliest productions. Old catalogues show the 146 positioned as the pen for men in "responsible positions".
Production of the 146 was suspended during the 1960s for one decade. When production resumed in the 1970s, the celluloid was sadly switched for resin! The 146 design changed slowly over time:
To begin with, the ink window shrunk and changed in material. The drawings here show the transition in ink windows from a 1950s celluloid 146 (left) with the medium window like mine, to the celluloid short window, then to the resin of the 1970s and 1980s, and finally the modern 146 (right).
Another key difference between the celluloid 146 and its modern counterpart is the cap top star. The celluloid 146 had a casein star (right in pic) which ages into a beautiful ivory colour in comparison to the stark white modern MB star (left in pic).
Also, the 146 has grown longer over time. From left to right in the picture, we have the 1949 model, a late 1970s model, and a modern 147. The 147 is a cartridge filler, and it needed to make space for the two cartridges it houses. Hence, it needed to be longer than the standard 146. But, since the 147 was essentially designed as a 146 with a cartridge system - a "traveller" version of the 146 - MB required both pens to have identical dimensions. This led them to increase the size of the 146 to match the 147.
The nibs on the 146 have changed over time too. The earlier nibs were two-toned 14c nibs that are known to have some flex (left in pic). Then in the 1970s-80s the resin body and blue/grey window 146 sported a soft monotone nib (middle in pic) that is well-appreciated by collectors today. The modern version presents a rigid two-tone nib (right in pic).
Finally, the celluloid 146 was first fitted with the innovative telescopic piston which promised double the capacity of ink because of its two-stage system that collapses into itself (as shown in the picture). Only the top tier 13x, 14x, and 24x pens had the telescopic mechanism. But the complexity of this mechanism proved unfeasible for continued production. Hence, in the 1960s, the 146 pistons took the design of the more reliable modern fillers.
The 146 has endured the test of time because it is still one of the most popular Montblanc pens available today and is largely unchanged in design.
Rösler, J., & Wallrafen, S. (2001). Collectible Stars: Montblanc-Schreibgeräte von 1946 bis 1979.