Gwindel, smoky quartz, Adular – Val Giuv, Graubünden, Switzerland
 Gwindel with the sought-after intense "Coca-Cola" color, characterized by a reddish, smoky brown. The sharp-edged and highly lustrous crystal is crystallized even at the base.
 The Val Giuv, near Sedrun in the Surselva region of 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 prospectors at an altitude of approximately 3,000 meters.