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Ink Reviews

Whoa! Montblanc Inks…Beware!

Ink swatches with handwritten color names.

Happy New Year, everybody!

Sorry for the long absence. December and early 2022 have been quite the rollercoaster. Happily, all is well now, and we hope to be back to rockin’ and rollin’ the ink-o-sphere.

Wow! Three months in the sun fades the pigment right out of modern Montblanc inks. Mont Blanc ink burns worse than I do in sunlight.

The biggest shock to me in Dawn’s and my ink tests comes from Montblanc! At $26 retail for a 60ml bottle of ink, you’d think you’d get something close to perfection…especially with the company’s luxury marketing! It is worth it to do a little math here. A 60ml bottle of ink at $26 per bottle means the price of a single milliliter of ink is 43¢. A U.S. gallon is a shade over 3,785 milliliters. Ergo, a gallon of Montblanc ink costs $1,627.55! A gallon of gasoline here in Norwich is $3.39, and a gallon of milk can be found for $4.29. It will seem as though gas and milk are a better bargain, especially after these results.

Now before you start thinking I’m being completely unfair to Montblanc, I’ve always liked its ink. At pen shows I use it as my test ink for anyone wanting to dip a nib to try out a pen. When people asked me what was one of the safest brands of ink…based on no research but word of mouth around pen shows…I’d usually tell them they could trust Montblanc best.

I hereby rescind that proclamation of safety. I got my first wind that trouble was in the air when a customer returned a pen to me after only 3 or 4 months of use with Montblanc Mystery Black ink. Its rubber ink sac had melted. At the time, I thought that was weird and worried the customer had used something far more toxic and then tried to cover it up with Montblanc Mystery Black. Nope. I doubt that now.

Back in July, 2021, I stuck a sample of 8 new bottles of modern Montblanc ink swatches in my sunniest window. These inks included: Oyster Grey, Midnight Blue, Irish Green, Toffee Brown, Royal Blue, Lavender Purple, Burgundy Red and Mystery Black.

After only 3 months in the sun, nearly all faded out! Royal blue turned a faded green. Irish Green and  Lavender Purple almost went invisible.

When Dawn and I tested the fresh ink’s pH, we were equally surprised. For a quick chemistry refresher. Everything is measured in pH on a scale from 0 (extremely acidic) to 14 (a base that is extremely alkali). 7 (distilled water) is perfectly neutral. We calibrated our pH tester at 24.6ºC.

Here are our results from the Montblanc ink pH Test:

Mystery Black          4.3
Royal Blue                3.8
Burgundy Red         4.8
Midnight Blue         4.2
Irish Green               3.9
Oyster Grey              3.9
Toffee Brown           5.6
Lavender Purple     3.8

All of these inks are quite acidic. Blue and black inks are supposed to be the safest inks. They are very acidic in Montblanc! Now, we aren’t chemists. We do not know how the chemistry between the ink sacs, pistons and converters interacts with the ink. Yet, this raw data casts doubt on the safety of Montblanc ink. Perhaps it is the special “cleaner” Montblanc uses to keep inkfeeds clear that is to blame for the acidity. The company recommends only using MB ink in MB pens. Perhaps there is more to that than just their greed of simply wanting to sell more ink.

As we still have a few of the old bottles of Montblanc ink from the 1990s, we didn’t do a UV test on them, but we did a pH test and it was even worse.

Black          2.2
Turquoise 2.8
Red            6.5
Green        3.0

Maybe you’ve had great results. I certainly don’t want to ruin your faith in Montblanc ink, if it has always worked for you. However, it might not be the gold standard I once thought it was. The information here is simply raw data, but it seems striking.

Last reviewed July 25, 2025 · Drippy Musings is the ThePenMarket.com blog

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