Smoky Quartz var. Gwindel with Adularia

This fabulous plate of Alpine minerals is from the Giuv Valley in Grischun, Switzerland, an area of high mountains and spectacular Alpine scenery.  This beautiful specimen just about fully characterises what Alpine mineralisation is all about with Smoky Quartz crystals; a Smoky Quartz Gwindel and chlorite-tinted Adularia crystals scattered over.  All the Quartz crystals are transparent, and most would be classed as gemmy.  They are pale clove to light Champaign and range from a few millimetres to 2.5 cm tall.  The main Quartz feature is a beautiful Gwindel, some 4.8 cm long and composed of eight slightly rotated Smoky Quartz crystals.  The variety known as Gwindel Quartz appears to be slightly twisted, whereby the apparently stacked Quartz crystals slowly rotate about their common c-axes.  The overall degree of rotation can vary greatly in Gwindels, and in this case is most apparent with a progression of about 45 degrees from start to finish.  Adularia is the glassy variety of potassium Feldspar, typically Orthoclase.  Large milky-white rhombohedral crystals form clusters to 4 cm across over the matrix and surrounding the Quartz crystals.  The Adularia is translucent and dusted and included with pale sage-green Chlorite.  A delightful large cabinet specimen of a Smoky Gwindel, Smoky Quartz crystals and Adularia from the Giuv Valley in Switzerland.