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, flat-lying cubanite crystals to 7mm in size. Apparently this specimen was exchanged to the Academy by the Smithsonian. Ex. Philadelphia Academy of Sciences and Smithsonian Institution Collections.
Attribution: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0
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