Trapiche emeralds hail exclusively from the emerald mines in the Boyac region of Colombia, and are so named because their patterns resemble the spoked wheels of the heavy gear locals use to grind sugar cane. Extremely limited in supply, trapiche emeralds are perhaps the rarest of all "pattern" gemstones. Their six distinct "spokes" are caused by the presence of the mineral inclusion lutite. As the hexagonal emerald crystal grew, it pushed the lutite towards the center of the crystal and then radiated out in the six directions of the emerald crystal. A truly remarkable feat, compliments of Mother Nature!