#333Diamond Facet Sparkle

A brilliant-cut gem — the convex intersection of a table, eight crown and eight pavilion half-spaces — turning slowly under a single key light. Every view ray is sphere-traced to a razor-flat facet; the facet normal drives a spectrally dispersed sparkle (hue smears with NdotL and view angle through a rainbow palette) while a tight specular lobe ignites bright fire whenever a facet swings edge-on to the light. A filmic knee caps the flashes so the stone glitters without blowing out. Hover to steer the gem, press to stoke the fire, scroll to spin it.