High-grade pitchblende (uraninite) from the historic Mi Vida Mine in San Juan County, Utah, launched the 1950s Colorado Plateau uranium boom when geologist Charles Steen cored through a 14-foot-thick deposit of dense, radioactive ore in July 1952.
Key Details of Mi Vida Pitchblende
• Discovery and Geology: The ore body was discovered at a depth of 197 feet in the Moss Back member of the Chinle Formation in the Big Indian district near Moab, Utah. Read more about the historical background at MiningIR.
• Composition and Appearance: Uraninite (UO₂) from the mine appears dense and metallic, often associated with pyrite, chalcocite, and bright yellow secondary uranium minerals like uranopilite.
• Radioactivity Levels: Smaller specimen fragments typically emit 85,000 to 200,000 counts per minute (CPM) on digital scintillation counters like the Radiacode, while massive museum-grade vein specimens can exceed 1,000,000 to 1,750,000 CPM.
• Collector Market: Surviving high-grade pieces from the exhausted and collapsed mine are rare and traded among mineral collectors.
Mi Vida Mine, Utah
7x5x2 cm
95 grams
🔥 700,000 cpm on Radiacode 110
S2