Galena with Chalcopyrite and Quartz Willard Wulff which is likely to be

which is likely to be caused by a micro amount of oxidized Cuprite on the surface of the specimen

and rare light green Paravauxite crystals on the back/reverse side of the specimen

From a find in June of 2007

If you’re in the market for a large and impressive Cassiterite twin from Viloco

Galena with Chalcopyrite and Quartz Willard Wulff which is likely to beA bright and eye catching cabinet sized display specimen featuring predominant, sharp, cuboctahedral groups of silvery Galena which are perched atop Chlorite included Quartz crystal matrix. The Galena groups have a selective deposition of bright, sharp, lustrous golden Chalcopyrites, creating a stunning two tone color effect. Many of the Galena crystals actually have Quartz crystals growing right through them! The piece is in great shape on all sides,