Perle Noir is one of the most recommended and well reviewed black inks out there. When I bought this ink a few years ago, I was disappointed. It is not the blackest, not the smoothest, not the fastest drying ink, not an archival ink, not the cheapest. I decided to give it a second chance so I eyedropped a Preppy with it and filled a Lamy All-star. Over the past few days I have written many pages of work notes with the ink. Perle Noir is a well behaving black ink that is sold at a reasonable price, but it doesn't excel in anything. Below some writing samples, followed by drying times and test in water resistance. Drying times are about average to slow, 45 secs with a broad nib on Tomoe River 52g paper. The ink is certainly not water resistant, but it can handle an accidental drop. The full characteristics: Feathering none Shading hardly any Show through negligible ...
Iroshizuku has recently launched a series of limited edition inks, based on the Japanese Gods for luck. A clever marketing scheme, at 1.5 the normal retail price and colors that are not always easy to distinguish from the normal collection. Try to do a proper blind test between Murasaki-Shikibu and Jurosin for instance. I wouldn't bet on my ability to always tell these two apart without a paper chromatography.
But, arguably, Iroshizuku makes the best inks in the world, so let's give them some credit. And, truth be told, some colors are a welcome addition to the portfolio.
The color I do like best from these limited edition series is Hoteison. A very dark green (almost black). The ink behaves perfectly, flows smoothly, has a nice subtle shading and is a dream to write with in any fountain pen. Of course this ink deserves high quality paper.
The color is neutral enough for a business environment. No one would frown upon notes or signatures in a black green color. I'm not too sure about personal correspondence, I think it lacks warmth for it, or something that would really set it apart from other colors. Being neutral comes at a price. At the same time, I can easily think of a few subjects to write about that would really be suitable for this color.
It was hard to find comparable colors in my collection. Take-sumi by Iroshizuku is a black, Vert empire by J. Herbin is a darker green with low saturation but way lighter. Maybe Moss Green by Graf von Faber Castell comes close but is still considerably lighter.
N.B. Writing is on Original Crown Mill Vellum paper.