Opalescent Fluorite (unique material) (ex Kay Robertson Collection)

Item Description

The Clara Mine in the Freiburg (not Freiberg) Region of Germany is one of the great localities in the storied history of mining in this country. Nearly 450 species have been found there! The mine has been operating since 1726, and as far as we know, is still currently active, as it is mined almost strictly for Fluorite and Barite (which are the main veins of mine - sometimes measuring up to 12 m across!) This piece is a unique or a least highly unusual specimen in my experience with Fluorites from this mine as it features a coverage of dozens upon dozens of sharp, lustrous, very gemmy cubes of Fluorite measuring up to about 3 mm which are actually a pale blue color underneath but have what is referred to "Opalescent" Fluorite on the label, which I can best describe a bright golden metallic iridescence on the surface of the crystals. The matrix is solid white massive Barite. A really special and certainly odd Fluorite for any fan of worldwide Fluorites or minerals of Germany. Don't miss out on this one as it is truly unlike another that I can remember seeing from this world-class locality. Ex Kay Robertson Collection (#4913). Kay was a prominent California collector, who specialized in European classics. She nearly lived 100 years from April 1920 - March 2020. See the article in the March-April, 2007 Mineralogical Record ( https://www.mineralogicalrecord.com/pdfs/Kay%20Robertson%20Collection.pdf ), and the 50+ page article in the German Magazine "Mineralien Welt" November-December 2017.