Chalcedony
Huh...weird name for a “band”...but then, why would a person nót call his project after a cryptocrystalline form of silica (composed of very fine intergrowths of the silica minerals quartz and maganite)? With its waxy luster, semi-transparant aspect, and assuming a wide range of colours (although usually white to grey, greying blue, or a shade of brown ranging from pale to almost black), I can certainly understand why the mineral may have spoken to the artist's imagination! (P.S.: mineral description taken from Wikipedia)