A muted moss green that darkens toward black on the page. Platinum makes it the old way, with iron, and it writes dry.
The maker, the year, the line, and the language of the name itself.
The primary read, the pool at the trough, the sheen at the angle, and how much the colour shifts as it dries.
The liquid itself: pH, lightfastness, how it behaves in the bottle and inside a demonstrator.
Wetness, saturation, sheen, shading, and how feathering and ghosting test on standard cream.
Seconds to a smudge-free pass on the standard cream paper.
Where this ink belongs in the cabinet: by nib, by paper, by occasion.