Pharmacosiderite

$5,300.00

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A particularly rich specimen of leafy oil green Pharmacosiderite forming cubic crystals, many to nearly 2 mm. These line several vugs up to 6.5 cm long in a hard, dark chocolate, rusty brown Goethite/Quartz gossan. This superb cabinet specimen is from Wheal Gorland at St. Day, in the parish of Gwennap, Cornwall, England. When Wheal Gorland was extracting the near-surface oxidised zone of the orebody in the second half of the eighteenth century, the village of St. Day did not exist, the closest conurbation being Redruth to the west. The Pharmacosiderite, a hydrated basic ferric arsenate, forms perfect, sharp cubic crystals with lustrous faces which sparkle from within the vugs. Under low magnification (say, x5) the crystals, although opaque, have a translucent rich leaf green outer surface which have an inner metallic lustre as if filled with crumpled reflective foil. A stunning display specimen of beautifully crystallised Pharmacosiderite from Wheal Gorland.