Kop Daglari in Turkey produced the world's finest kammererite until it closed in the early 1990s.  This piece came to me from a Turkish collector/dealer who was there the day the mine closed.  The display face is richly covered with flashy, lustrous crystals, all colored a rich magenta purple.  Kammererite is the rare chromian variety of clinochlore, and is much sought by collectors who are drawn to its vivid colors and sharp crystals.