Epidote (possibly Augite) (ex Kay Robertson Collection)

Item Description

An interesting group of "faden"-esque / parallel growth crystals of very dark, greenish black Epidote according to the label, but I think this could be Augite (Fassaite) as I've seen a couple specimens that resemble this piece. Both Epidote and Augite are monoclinic, so it's difficult to differentiate the two species by crystal habit. These crystals have a slightly different luster than the Epidotes I've seen from the area, and they are notably opaque, while most of the Epidotes from Gilgit-Baltistan are typically at least slightly translucent. With that said, it's certainly an old specimen as there is not specific locality given, and I would guess it dates back 30+ years to when some of the earlier "Alpine-type" material was coming out of Pakistan. Ex Kay Robertson Collection (#11202). 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).