"Adularia" (K-Feldspar) with "Moonstone" effect (ex Kay Robertson Collection)

Item Description

A sharp, well-formed, rather lustrous, blocky and partially gemmy white / colorless crystal of Adularia (a variety of K-Feldspar) with the classic and HIGHLY desirable "adularescence" or "Moonstone" effect which shows a shimmer when rotated in the light. The crystal has a very minor Clinochlore ("Chlorite") inclusions to create a slight two-tone effect. No damage that I can see and the crystal looks beautiful from several angles. These are classics from this well-known peak in the Swiss Alps. Ex Kay Robertson Collection (#12927). 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 Welt" November-December 2017).