Boracite (RARE twin) (ex Kay Robertson Collection)

Item Description

Specimens of Boracite from Sehnde are very few and far between on the market, especially matrix specimens. Not only is this piece a showy matrix specimen of these classics, but it features a RARELY seen penetration twin. Boracite twins on the {111} (octahedral) face, but to be honest, this might be the most well-defined twin I've seen for the species as the outer points of the crystals flare out like the wings of a bird. This twin has a rich golden-brown hue, measures 8 mm across and sits beautifully on the matrix. An extremely hard to find specimen and a great thumbnail of this classic material. Ex Kay Robertson Collection (#5761). 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).