Bournonite from Yaogangxian is considered by many as the finest in the world, with bright silvery, mirror lustrous surfaces and good more prismatic (rather than 'cogwheel') form. This is a good thumbnail sized crystal, partially double-terminated, and complete on both sides. From the collection of Lorraine Sofia, a local collector who considered herself to be a 'mini John Barlow\" and had a good eye for quality specimens.