Pharmacosiderite (rare locality specimen) (ex Kay Robertson Collection)

Item Description

A very hard to find specimen of Pharmacosiderite from Graul in the Ore Mountains of Saxony. Upon close inspection, one can see many sparkling, golden-brown colored, gemmy cubes measuring up to about 1 mm on matrix. This potassium iron arsenate is actually the namesake for its own group. Yes, the crystals on this piece are not big, but they look wonderful under magnification. Ex Kay Robertson Collection (#3326) with labels from the Pearse Collection of Harvard Univeristy and a dealer label from John Albanese. Kay Robertson 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).