Manganese Oxides var: Manganese Dendrites on Limestone

Item Description

A classic specimen of these now very seldom-seen specimens from near Eichstätt, a town in Bavaria, Germany. The limestone quarries in the area have produced some truly picturesque specimens of dendrites in limestone matrix, which found their way into collections around the world. This piece is a great example of the material featuring Manganese Oxide Dendrites (or possibly psilomelane) sitting on limestone to create what almost resembles organic imprints (a pseudo-fossil if you will). The dendrites formed in Jurassic-aged limestone which is actually famous for dinosaur fossils, so it would make sense that people thought these particular dendrites were fossils of one form years ago. Specimens of this size and fine quality are rarely available.
Ex Kay Robertson Collection (#5914). Kay was a prominent California collector, who specialized in European classics. She nearly lived 100 years from April 1920 - March 2020. See the article in the March-April, 2007 Mineralogical Record ( https://www.mineralogicalrecord.com/pdfs/Kay%20Robertson%20Collection.pdf ), and the 50+ page article in the German Magazine "Mineralien Welt" November-December 2017.