Quartz

Although definitely yellow, this quartz crystal isn't a citrine. In this specimen, iron has stained the matrix coating yellow but doesn't form a part of the quartz's composition. The iron causes a shimmering rainbow effect. 16.0 x 10.0 x 6.0 cm, Sils, Thusis, Domleschg, Grisons, Switzerland. © Rob Lavinsky, www.iRocks.com. Used with permission.

Article: Citrine Value, Price, and Jewelry Information

Credit: www.iRocks.com