Chalcocite pseudomorph after Covellite (ex Kay Robertson Collection)

Item Description

A fantastic pseudomorph from the famous Butte District in Montana featuring a superb crystallized rosette of Covellite that has been pseudomorphed by steel-grey Chalcocite. The largest "blade" on the specimen measures 1.2 cm. Minor Enargite and Sphalerite are present on the piece according to the label. These pseudomorphs are note easy to find on the market, and are highly sought after by Butte collectors. Valued at $800. Ex Kay Robertson Collection (#B1.2713). Kay is a prominent California collector, who specialized in European classics (see the article in the March-April, 2007 Mineralogical Record). A beautiful and attractive display specimen from this classic locality.