Libethenite is an uncommon copper phosphate. This fine old-time specimen from historic Cornwall, England features a well-place vein richly lined with sparkly, very dark green libethenite microcrystals in a 3-dimensional matrix of massive, dense, rich copper ore. Accompanied by an expertly handwritten, faded label from an older collection. The collection this came out of was a museum stash dating to prior to World War I.