Monte Rosa is not another maker's brand but a Montblanc range in its own right: inexpensive school and everyday fountain pens of the 1950s, named after another Alpine peak. The absence of an engraved, uncoloured star emblem on the cap top is normal for these models and no sign of a fake. The steel nib bearing the words “Monte Rosa” likewise belongs to the original, since the range was deliberately positioned below the Meisterstück.
Identification is made easier by the two-part imprint at the end of the barrel beside the piston knob: on one side the model number, 042 for instance, on the other the code for the nib. Here K denotes the ball-ground, smooth-running tip and the second letter the width, so “KF” is a ball nib in fine.
Condition matters more to the value than rarity does. Worn plating on clip and cap ring, or a nib worn shiny, push the price down sharply. Well-preserved Monte Rosas turn up regularly at collectors' fairs, and often cost less there than poorer examples do in online auctions.