Pyroxene with Tridymite (rare material and locality) (ex Kay Robertson Collection)

Item Description

An extremely rare specimen from the Ettringer Feld in Germany sharp, lustrous, prismatic crystals of a golden-brown Pyroxene species (according to the label) associated with the low pressure high-temperature-stable dimorph of Quartz, Tridymite in basalt matrix. Tridymite is SiO2, just like Quartz, but forms at at different temperature and pressure, and is not often seen in nature in crystals larger than micros. Now the Tridymite on this specimen is nothing exceptional, but it's CONFIRMED Tridymite, so it's incredibly rare and any species (or locality) collector should pick this one up! Ex Kay Robertson Collection (#8258). 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).