Fluorescent Barite from Elk Creek, South Dakota
Sprays of golden amber barite crystals cover a dark chocolate brown matrix in this specimen from the Elk Creek area of Meade County, South Dakota. Under both short and long wave UV the barite fluoresces a creamy white color, and phosphoresces blue/green after short wave and green after long wave. The Elk Creek area is notable for producing golden-amber colored barite crystals that are fluorescent under all UV wavelengths. The primary occurrence of this material is located along the bank of Elk Creek in the Black Hills of Western South Dakota, where the barite crystals have formed within the hollow interiors of calcareous concretions found in the surrounding Cretaceous age shale. The size of this specimen is 66 x 47 x 38 mm, and it weighs 86 grams.
Mouse over the scrolling images to see UV wavelength information.