Cassiterite on Quartz (ex Kay Robertson Collection)

Item Description

A classic specimen from this old tin / tungsten mine that dates back to 1892 (now completely closed and off limits due to its incorporation into a National Park). It should be noted that these specimens haven't come out for AT LEAST 50 years, and if you collect Cassiterite, it's a great specimen to add to your collection just for the locality. Several very lustrous, sharp, well-formed Cassiterite crystals measuring up to 4 mm are sitting on the prism faces of a gemmy to milky single Quartz crystal. A bit of associated golden-tan colored Muscovite is present is well. The front of the piece is in excellent condition, but there is a separation mark on the back of the piece where another Quartz crystal once grew. The Cassiterites are mostly black in color, but I can see tiny bit of golden and honey colored flashes with strong backlighting. Ex Kay Robertson Collection (#11981). Kay was 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).