Fluorite (color change crystals) (ex Kay Robertson Collection)

Item Description

It should be noted that this specimen came labeled as Freiberg, with no specific mine. Sharp, well-formed, translucent cubic crystals of Fluorite which show a blue color in indoor lighting, but a lovely green color in sunlight. There are actually two generations of Fluorite on the specimen as you can see a lone purple / lilac cube (measuring 2.6 cm on edge) that clearly was deposited prior to the smaller cubes. A classic old specimen from this incredibly famous German mineral producing district. Ex Kay Robertson Collection (#2333). 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). Valued at $950.