Rohrer & Klingner Fountain Pen Ink (50mL) - Eisen-Gallus-Tinte Salix (Iron Gall Blue)

This is an excellent tame iron-gall ink (and has since become my favourite blue. It's first a pure navy blue, but quickly turns to a blue-black when contacting air. It's very waterproof, and doesn't feather either. This makes it great for cheaper papers.

Now the downsides:
Its a very very dry ink. You can never get to that peak saturation unless you constantly saturate the feed. On the Pilot MR, its very faint. It works on the Safari well though.

I am loving the qualities of this ink. It's perfect for a left-handed overwriter. Dries reasonably quickly with no smudging. It's also one of those inks that is well behaved on a variety of paper qualities (and even shades on cheap paper too!). Very low feathering.

I hear from wonderpens and several online sources that this is one of the milder iron gall formulations out there (and modern iron gall ink is already much milder than it was in the distant past). Don't worry, it won't melt your pen. Use it in a wet writer as this ink is a little dry giving you some feedback from the nib (a pro for some, con for others).

It's bluer and has more character than Diamine Registrar's Ink. It looks similar to Iroshizuku's Blue-black "Shin-Kai" ink when used with an EF, F or M nib. It even demonstrates the same darkening colour change of that ink, and it's permanent.

All in all, it's one of my new favorite inks! Utilitarian, classy, and easy on the eyes.

This is what I have in a Lamy Safari that bumps around in the deep abyss of my bag everyday. Works well on all paper, and I mean every paper type, and will not feather. Extremely well behaved ink.

The ink smells a bit more than other regular inks and that's normal.

(This is mostly copied from my review for Scabiosa, as both inks are extremely similar)

Iron gall inks are corrosive and require regular pen cleanings, but their good qualities are worth it. Salix is a true blue-black with no purple or green tones. It goes on the page a vibrant blue then darkens to blue-black as it dries It has dramatic shading on high-quality paper, and on low-quality paper, it bleeds and feathers much less than any standard dye-based ink I've used.

This ink is highly water-resistant. If exposed to water, the blue component of the ink will wash away, but the grey component stays.

Though it flows well, it provides no lubrication whatsoever while writing. Even so, this is a great business-appropriate colour of ink, and may have to buy an entire bottle when my sample runs out.