Formula: (Th,U)(SiO4)1-x(OH)4x Tetragonal Description:Thorogummite is formed by the alteration of other thorium-rich minerals, such as thorite. IMA currently lists its status as a species as “doubtful.”MARATHON COUNTY: Much of the thorite found in the pegmatites of the Stettin …
Wood County
Tremolite
Formula: Ca2Mg5Si8O22(OH)2 Monoclinic Description: Tremolite marble from Florence County, Wisconsin. Field of view 7 cm across. (Photo by Al Falster.) Tremolite is formed by the metamorphism of calcium-rich rocks such as limestone and dolostone. It occurs in numerous …
Uraninite
Formula: UO2 Isometric Description: Uraninite with pen for scale. From the mineral collection of Brigham Young University Department of Geology, Provo, Utah, Mineral Specimens 1134. Courtesy of the U.S. Geological Survey Denver Library Photographic Collection. (Photo by Andrew …