An absolutely superb Chinese bournonite composite cluster on a quartz crystal matrix. There were many very good Yaogangxian bournonites on the market at one time, but their availability has diminished significantly in the last decade since a collapse of a pillar used to support the shaft in that region of the mine led to tragic deaths as it was robbed of specimens. This piece is exceptional in composition for its size class and for the spatial arrangement of the bournonite crystals that all seem to be in parallel and slightly offset growth. You have here a LOT of visual impact and volume, for the balanced size which is fitting for so many collections. It has impact, from the aesthetics and positioning of the silvery crystals on the quartz, showing off the terminations in a frontal view. Most of the individual crystals are discernible cogwheel twins. A bright and attractive specimen that is worthy of any great display collection, it is an old specimen from Ken Roberts' collection (he travelled to China over 100 times in the heyday). The piece presents well on a custom engraved acrylic base.