Uranophane

Uranophane. From the mineral collection of Brigham Young University Department of Geology, Provo, Utah, Mineral Specimens 1145. Courtesy of the U.S. Geological Survey Denver Library Photographic Collection. (Photo by Andrew Silver.)

Formula: Ca(UO₂)₂(HSiO₄).5H₂O Monoclinic

Description:

Uranophane and petrified wood from Henry Mountains, Utah. From the mineral collection of Brigham Young University Department of Geology, Provo, Utah, Mineral Specimens 1147. Courtesy of the U.S. Geological Survey Denver Library Photographic Collection. (Photo by Andrew Silver.)

Uranophane is a bright yellow mineral formed by groundwater alteration of other uranium minerals.

MARATHON COUNTY: Found at the Summit Mine, about 3 miles NW of Wausau at the intersection of County O and U. It forms thin yellow coatings on fluorite, and K feldspar. (Weidman, 1907b, Pallen, 1963).