Rohrer & Klingner Scabiosa Iron Gall Ink

Rohrer & Klingner Scabiosa is a purple fountain pen ink that's permanent and lightfast. If you want people to be able to read your notes in 300 years, this is the ink you'd want to use.

This is iron-gall fountain pen ink, which means it's waterproof. Though it's less acidic than old-school iron galls, it can corrode steel nibs if left to dry on them. I recommend using this with gold fountain pen nibs. If you want to be on the safe side, Rohrer & Klingner recommend that you clean your pen once a week while using iron-gall ink.

 Made in Germany.