Each Rhino layer keeps its own material. The quick colour swatches set all layers of that kind.
Metal
Metal HDRI
Diamond / Gem
Gem HDRI
HDRI Rotation
Metal HDRI
Diamond / Gem HDRI
Camera
Studio
Background
Contact Shadow
Tone & Lights
Light Shadow
Viewer
Mouse/touch: rotate · wheel/pinch: zoom · right-drag: pan. GLB materials named DIAMOND / GEM / ROUND are treated as gems; other meshes are treated as metal.