Metavoltine (?) (ex Kay Robertson Collection)

Item Description

This toenail sized specimen came labeled as "Metavoltine (?)", and I'm inclined to agree, although the color is darker than virtually anything we've seen from the Cetine Mine in Tuscany. The piece features many clusters of sharp, lustrous, gemmy, dark orange colored (a somewhat reminiscent color to Orpiment) micro crystals of Metavoltine on host rock matrix. The piece looks beautiful under magnification, and we have photographed it with a Canon MP-E 65 mm macro lens to better illustrate the quality. If you collect rarities, don't miss out on this one as Metavoltine specimens are rarely available on the market, and some of the finest examples in the world are those from the Cetine Mine. It is Interesting to note that according to mindat.org, this species "belongs to a small group of ferrous-ferric sulfate minerals, that also contains bílinite, copiapite, römerite (purely Fe minerals), pertlikite and voltaite". Ex Kay Robertson Collection (#8006). 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).