A unique pocket of blueish iridescent chalcopyrite and brassy pyrite was found in 2013 from advance mining in the Borieva Mine. The matrix is galena and the pyrite and chalcopyrite either aggregated in rich clusters or as isolated ball-like groups on the galena. This specimen is a very fine example of the rich assemblage on matrix and is in great condition. Would compliment any Bulgarian or Eastern European collection.