Nonegon 

This nonagon is composed of three sets of three isosceles triangles, each with a 40° apex and 70° base angles. The three types of stone are Deer Isle Granite, Labradorite, and Larvikite. The green Labradorite from Madagascar and the blue-black Larvikite from Norway are iridescent; they glow from within as light is reflected between thin mineral lamina in the stone.