Lustrous, octahedral siegenite crystals reaching 5mm are scattered on white dolomite. Some are coated in microcrystalline chalcopyrite and there are a few chalcopyrite crystals reaching 1mm on the dolomite. Attractive thumbnail in excellent condition and a great example of this rare species. Ex Mark Shathin collection; the collectors label states Buick Mine but the specimen looks more typical of material from the Sweetwater mine.