Variscite with Crandallite

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A gorgeous large nodule of deep green variscite, much yellow crandallite present as well. Wardite is also present. This has been cut and polished on one side typical of this material. This is classic material for the locality, the color much better than most.The Green Monster mine, located on the southern slope of Little Mountain near Fairfield in Utah County, Utah, is a famous historic locality known for producing highly sought after phosphate mineral specimens. Geologically, the deposit is hosted within the Mississippian-age Great Blue Limestone formation, where brecciated and fractured limestone layers underwent intense alteration by low-temperature hydrothermal fluids. These migrating fluids dissolved silica and calcium while introducing phosphorus and aluminum, precipitating an array of colorful rare phosphate minerals like variscite, wardite, crandallite, and millisite directly into open nodules and fractures. Discovered in the late 1890s, the property saw its first major operational period between 1894 and 1900 under the direction of Frank Butt, who excavated several shallow pits and tunnels primarily to mine variscite as a gemstone under the trade name utahlite. Intermittent private mining and exploratory operations continued through the mid-twentieth century, with the most productive modern specimen recovery occurring during private leasing operations in the 1970s and 1980s, after which active collecting ceased as the site became dormant and strictly closed to the public.