10. Ijzergalnoten blue/black - Akkerman fountain pen ink

The faceted ink bottle is distinguished by its long neck, which contains a glass marble. Akkerman fountain pen ink is suitable for any type of fountain pen and available in 31 sparkling colors. The ink colors have been given names with a Hague twist

What makes this bottle so unique? By tilting the sealed ink bottle, the neck fills with ink. Set upright again, the marble falls back and prevents the ink from flowing back. This creates a reservoir of ink above the marble from which the fountain pen can be easily filled, even when the bottle is almost empty.

#10 Iron gall blue/black

Marble gall used to provide ink; gall nuts were an important ingredient in the ink that older people among us can still remember well, large bottles of ink with which the inkwells in school desks were filled. Since the Middle Ages, writing has been done with gall nut ink. The recipe also says: use a rusty nail – this does create a risk of iron gall corrosion in your paper.