I have recently returned to using one of my Montblancs purchased in the 1980s - a 144 fine/medium fountain pen. In going through my old stash, I've discovered MB blue-black ink cartridges that date from, perhaps, 1985. (The price on the box is $2.25, to give you an idea of the age.)

Are they likely to still be usable? Or would some of the moisture have evaporated, leaving something that would gunk up my Montblanc?

Thanks.

I am still using some (at least) 20 year old Waterman cartridges, I bought a whole bunch of them at once to go with my Gentleman FP. I would think, at worst, you might have to add some distilled water to those that might have lost volume, just remember to shake well after putting the water in. I suggest you do it outside of the pen. Don’t ask how I know that last, please, it is still embarrassing to remember. At least that is the most I have ever had to do with these, and that only with a couple of them.

(Just pulled some out and it looks like I may have to do the above with most of the ones remaining, the ink is getting pretty low and awfully thick looking. I think it is pretty easy to tell I don’t use my Waterman Gentleman very often, I am not really a cartridge user, and hardly more often a converter user.)

I don't recall where but I did read that you shouldn't be using any ink cartridge old enough for having evaporated... they say something such as 10 years tops or something.

Blue-black, in particular, has a lot of iron in it(since it is the only permanent ink in MB's line). I would buy new ones...they're only $3 now. If only their pens increased at the same rate...

I've injected a cartridge here and there with sterile distilled water from a sterile syringe to compensate for evaporation, if the amount lost was less than 1/3 of the cartridge volume, and had no troubles. However, I only did this if I was a) desperate, and using the cartridge up in less than two days.

I presume you don't need sterile distilled water, but I had it at the time, so why not?

Otherwise, if the cartridge is home to dried or sludgy gunk, I clean them out and refill them a few times. It's a way to recycle the plastic, and in a pinch, avoid purchasing another converter.

Toss 'em. All my old boxes from the 70s are toast, and yeh, the new ones are cheap. Nicer colors too - Sepia and Bordeaux are my favorite.