Iridescent Chalcopyrite w/ Pyrite (fine old classic) Robertson Coll.

Item Description

Sharp, striated, chalcopyrite sphenoids with beautiful golden-metallic iridescence are richly clustered on the front of the mounded matrix totally covered with tiny sparkly pyritohedrons. The chalcopyrites, to 1.5 cm, spill over onto the back side of this exceptional 360-degree old-timer from the historic mines at Freiberg. Ex Kay Robertson Collection # 7347 and acquired from Western Minerals in 1974 in San Mateo. Kay is a prominent California collector, who specialized in European classics (see the article in the March-April, 2007 Mineralogical Record and the 50+ page article in the German Magazine "Mineralien Welt" November-December 2017). Undoubtedly old-time material, but no proof. Chalcopyrites of this quality and richness in combination with pyrite are RARE from Freiberg.