The Mystery Black ink cartridges are a favourite, simple, sophisticated and a classy colour when writing. This popular colour within the Montblanc world is a high-quality ink and is designed to be fast drying to help limit the number of smudges on your page; this ink works with fountain pens that take cartridges. The cartridges are small and transparent so you can see the dark coloured ink inside; they come packaged inside a small Montblanc slide-out box neatly lined up inside.