Pyrite crystals on slightly iridescent Chalcopyrite matrix from Cavnic Mine, Maramureș County, Romania. A striking specimen from the renowned Cavnic Mine, Maramureș County, Romania featuring lustrous pyrite crystals perched atop a matrix of slightly iridescent chalcopyrite. The pyrite displays metallic gold brilliance, contrasting beautifully with the subtle, multi-hued sheen of the chalcopyrite matrix—an effect typical for this classic locality. The Cavnic Mine is celebrated for producing world-class sulfide mineral combinations, and this piece exemplifies the locale’s quality with excellent crystal form and visual appeal. Such combinations of pyrite and chalcopyrite, occasionally with iridescent surfaces, are highly sought after by collectors for their vivid aesthetics and mineralogical significance. The Cavnic Mine in Maramureș County, Romania has not been operating since 2008, when all mines in the area were closed, the adits were sealed, and external infrastructure was demolished or is in the process of demolition.