My recent buy of the KWZ inks got me interested again in Iron Gall inks. Years ago I had a bottle of P.W. Akkerman's iron gall ink (in Dutch: IJzer-galnoten) but never replaced it. The bottle itself is amazing. Practical because of the reservoir (sealed off with a marble) on top and a gem on every bookshelf.
The ink itself is a very sturdy and practical blue-black ink (but definitely grayish too when dry. It is perfect for the office, but there is no reason not to use it for personal notes or letters as well. The color may not be very vibrant or cheerful, but it's a good, solid, beautiful ink.
The ink is a bit dry, but behaves extremely well. Writing is smooth. No feathering, decent shading, minimal show-through. Drying time on Crown Mill Vellum paper is less than 15 seconds, fast! This iron gall ink definitely has registrar qualities, it is not afraid of water. You don't even see on the grid where I dropped water. And a separate two hour soak-in-a-cup test didn't harm the ink either.
So what does it compare to? The gray/greenish color it dries up to sets the ink apart from others. IG Blue #2 by KWZ is a darker blue. Blue nuit (Herbin) and Shin-Kai (Iroshizuku) come close when the ink is wet, but the difference gets bigger when the IG dries and darkens. N.B. This scan was taken more than a day after writing.
I will keep a pen filled up with this ink for a while.. I really like this ink!