Gahnite (Spinel Group) (ex Kay Robertson Collection)

Item Description

Gahnite is a rare zinc-bearing member of the Spinel Group that was named in 1807, but the species has been known prior to its naming. This thumbnail specimen is a rarely seen example from the famous locality at Broken Hill in New South Wales, Australia. The entire Broken Hill District is among the mineral producing areas in the world in terms of diversity of species (over 340 reported - https://www.mindat.org/loc-235733.html ) and fine quality specimens. This specimen features several very sharp, well-formed, nearly black (very dark green) crystals of Gahnite measuring up to 6 mm, sitting in massive slightly smoky colored Quartz matrix. The crystals are not the typical octahedral habit that one would expect from a Spinel species, but rather show clear dodecahedral faces along with octahedral modifications. A must have for any fan of Spinels, thumbnails or minerals from Broken Hill. Ex Kay Robertson Collection (#7264). 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.