Stillwellite-(Ce) (very rare) (ex Kay Robertson Collection)

Item Description

Stillwellite-(Ce) is a rare REE borosilicate and some of the best crystals of the species originate from the rugged mountains of Tajikistan. This is one of the better crystals collected from a remarkable pocket in September of 2004. It features a 6 mm, translucent, medium brown-yellow (normal indoor lighting) crystal on Quartz matrix. The fact that the crystal passes any light is noteworthy, as the species can be dark and "earthy". Interestingly, the crystal shows a color change from reddish-orange hue in halogen or sunlight to more of a yellow tone in fluorescent light. This is a very fine, mostly complete crystal for the species, as well as being unusually attractive with defined crystal faces. From an old find not repeated since. Ex Kay Robertson Collection (#7819). 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).