Pilot Iroshizuku Yama-budo (“crimson glory vine”) is a dark purple, closer to fuchsia, with gold sheen and some shading.
Scans
It’s a slightly different color on each paper, but very close. There is at least a little shading on each paper type.
Photos
The sheen is gold, though occasionally it looks a little greenish. As usual, it shows a lot in the large swatches but not much in the writing.
There are traces of sheen around the edges of lines and shading, but not a significant amount.
Microscope
The sheen sticks to the edges of lines and some foreground fibers, it does have slightly more coverage here and there.
Chromatography

It starts with a gray line that fades into a large magenta area, after that stops it fades into a dark red band.

The whole area near the end glows extraordinarily bright red.
UV Check
It’s all glowing bright red! The writing and the swatch are all glowing to varying degrees. Lighter ink coverage glows brighter.
Verdict
This is another winner! It’s a superb color with all the standard Iroshizuku ink benefits plus a fluorescent bonus. I’ve used it in a wide variety of pens with great success.
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