Pilot Iroshizuku Fuyu-gaki (“winter persimmon”) is a warm and readable orange ink with a little sheen and very little shading.
Scans
The scans look much more red-orange than it does to the eye. Iroful is a tad lighter than the other papers, but they are all orange.
Photos
The sheen is a bit odd on this one. On col-o-ring it’s barely there, only some gold around the edges. On Iroful there is small amount around the boundaries of heavy ink areas. However, on MD it’s quite heavy and changes from gold to more of a silvery color. It doesn’t show like that in the writing, so maybe it went down a bit too heavy when I swatched it.
Microscope
The color under the microscope is a better representation of its general appearance. You can see a tiny amount of gold sheen around the edges of lines and more in the large swatches.
Chromatography

The chromatography fades into magenta and then yellow-orange with dark orange around the edges.

Under UV the magenta area glows bright yellow(‽) and the orange area glowed orange.
UV Check
Much to my surprise, it glows much more than expected under UV. Mostly different shades of orange with a couple areas being more red in the swatch, while the writing glows orange evenly. It’s not terribly bright, but it’s not subtle either.
Verdict
This was my first orange ink, purchased as part of a four-ink set of 30ml bottles of Iroshizuku inks. Before I used it, I wasn’t sure I’d even like orange inks, but surprisingly, I do! I’ve acquired a few other orange inks after this one, but this is still my favorite.
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