One of the largest and most dramatic specimens from this one-time find in rural China, of chalcocite liberally coated with chalcopyrite. The bubbly growths are djurleite, also coated with chalcopyrite, and perched on chalcocite crystals in the core of the cluster. We had a source right at the mine on these, and I spent several trips to China in 2012-2013 trying to lock up the good ones. This remains one of the more surprising finds from China in recent years. See our recent articles in the Mineralogical Record (Jan 2014) and in Lapis (in German, summer 2014) on this remarkable find, also available online at available as a blog post at http://www.irocks.com/tongshan-china-minerals-chalcocite-chalcopyrite-djurleite-2013. Joe Budd photos.