This flat presents a selection of Metamunirite and Phurcalite crystals from Utah, USA. The specimens mainly consist of light colored, white to yellowish mineral areas that occur as flat coatings or extensive coverings on the grey host rock. The crystals typically form dense aggregates and crust like growths, creating strong visual contrasts with the fine grained matrix. Color variations range from pure white to pale yellow and more intense yellow zones, giving the specimens a well structured appearance. The illustrated flat shows exactly the offered assortment and is offered as a unique flat.
Geology & Origin
The localities in Utah are among the classic sites for secondary uranium minerals in the United States. Metamunirite and Phurcalite formed in the oxidation zones of uranium bearing deposits through the alteration of primary uranium minerals under the influence of phosphate rich and uranium bearing solutions. These processes result in characteristic yellow to white uranium phosphates that commonly occur together. The region is internationally known for its wide variety of uranium minerals and represents an important reference area for the study of secondary uranium mineralization.