A SPECTACULARY LARGE and TRANSLUCENT vivianite crystal from the famous famous Blackbird Mine of Idaho, source of the finest US vivianites. This lustrous, black crystal is complete all-around and has a sharp termination. The two opposing sets of growth striations are fascinating, one paralleling the length of the crystal and the second set of striations paralleling the termination. SURPRISINGLY, this thick, black crystal has superb translucency! Most of the crystal is a gorgeous rose-red, with the lower third being green, as seen with backlighting. A large and important specimen of the species and famous location from the John Ydren Collection.