Quartz / Calcite / septarian nodule (very unusual material) (ex Kay Robertson Collection)

Item Description

This material is rather unusual and features according the the Mineral of the Month Club they are a "Quartz cast after the crack-filling of a septarian nodule or possibly after a similar crack-filling spherulite," according to former Smithsonian curator John S. White." It is an absolutely fascinating-looking specimen, like a fossil of some strange early life form. It is complete and undamaged all around. THIS piece is even more interesting as the "holes" of the specimen are still filled with white semi-nodules of what I believe is Calcite. Ex Kay Robertson Collection (#4233). 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).