Cubanite With Maucherite, Valleriite
Mackinaw Mine, Monte Cristo, Snohomish County, Washington, USA
Cabinet, 12.6 x 9.2 x 5.1 cm
Ex. Philadelphia Academy of Natural Sciences
A hefty ore specimen, with probably tons of material stuck inside it as well as what you see on the outside, judging by the look of it. I think the cubanite (and associated more rare species) fills thin fracture seams within. On the exposed main face, there are dozens of thin, flatlaying cubanite crystals to 7 mm in size. I had never seen cubanite from a US locality, before. According to the MINDAT entry on this mine, it produced ore from 1900-1910. Apparently this specimen was exchanged to the Academy by the Smithsonian. I am not sure if the reference on the Smithsonian label indicates this particular piece was referenced in 1958, or just the locality itself, in that article.