Serpentine pseudomorph after Hornblende (rare) (ex Kay Robertson Collection)

Item Description

An odd and rare specimen featuring a 4.3 cm long pseudomorph of dark greenish-black colored Serpentine which apparently (according to the label) has formed a pseudomorph after Hornblende. Additional spots of Serpentine pseudomorphs can be seen on the specimen, but the main group is the focal point of the specimen. This is certinaly the only specimen of this material that we've seen, and would make a superb addition to a suite of Alpine minerals or unique pseudomorphs! Ex Kay Robertson Collection (#4824). The piece is accompanied by a letter (written in German) from the "Insitute for Mineralogy, Petrogaphie, and Economic Geology" in Clausthal-Zellerfeld, Germany dated June 30, 1961 that confirms this piece is a pseudomorph of Serpentine after Hornblende. Kay 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 Velt" November-December 2017).