Willemite, Calcite and Fluorite from the Southwest: Hogan Claim, Arizona

Under normal daylight, this is a rather nondescript looking rock, but when viewed under UV it explodes with color in a spectacular multi-wavelength fluorescent response. This specimen contains willemite, calcite and minor fluorite, and was collected from the Hogan Claim (Hogan Mine), Wickenburg area, Yavapai Co., Arizona, in 2002. Under short UV the calcite fluoresces red, the willemite green/white, and the fluorite glows deep blue. The willemite also shows lasting phosphorescence after the short wave lamp is shut off. Under mid wave UV the calcite dominates with red fluorescence. Long wave UV brings out the blue fluorescent fluorite. This specimen is most spectacular when viewed under full-wave UV (short wave + mid wave + long wave). The size of this specimen is 8.1 x 7.0 x 5.4 cm, and it weighs 352 grams. The Hogan Claim is a former fluorspar (fluorite), silver, gold, lead and molybdenum mine, and is located near Red Picacho Peak in the Wickenburg area. It is also located on the same mountain as the Purple Passion Mine, another prolific source of fluorescent mineral specimens.

Click on the above images for a larger view and UV wavelength information.

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