Siderite (2 generations) (ex Kay Robertson Collection)

Item Description

This is a classic specimen of the elusive Siderites from the Farmsen Clay Pit in Hildesheim. I can only remember seeing one of these in person other than this specimen. Highly compressed, beautiful chocolate brown colored rhombohedra of Siderite sit atop a prior generation semi-iridescent spherical Siderite which formed over Septarian nodule matrix. Really attractive and VERY hard to find on the market. One reference I found online stated that these specimens were collected in 1958. Ex Kay Robertson Collection (#1747). 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). A fantastic German classic from the obscure locality. Valued at $800-$950.