Indicolite Tourmaline on Muscovite (Robertson Coll.)

Item Description

A 1.1 cm, gemmy to translucent, terminated indicolite tourmaline crystal with fine two-toned teal-blue color is aesthetically set on the laminated, pearlescent, muscovite plate. There is a smaller crystal on the back side. These are surprising indicolite tourmalines from this extinct Keystone District, South Dakota pegmatite mine. One usually thinks of famous California or New England pegmatites for US indicolites, not South Dakota. Ex Kay Robertson Collection # 621, acquired in the mid to late 1950s, with the low collection number and comes with a copy of her label. 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). Very rare on the market today. A must for the locality or species collector.