Gwindel, Smoky Quartz, Adular – Val Giuv, Grisons, Switzerland
 
Gwindel with the sought-after, particularly intense, dark "Coca Cola" color, which is characterized by a reddish, smoky brown. The highly lustrous and clearly defined Gwindel is accompanied by a few crystals in normal habit. 
 
The Val Giuv, near Sedrun in the Surselva in the canton of Graubünden, has always been synonymous with the special color and quality of Swiss smoky quartz, which distinguishes it from other quartz.
Under the most difficult conditions, the crystals are recovered by the emitters at an altitude of around 3,000 meters.