URANOPILITE
Specimen urp-1
$ 28.00Dims: 3.4" x 2.7" x 1.5" (8.6 x 6.9 x 3.8 cm)
Wt: 5.83 oz. (165.5 g)
Mi Vida Mine, San Juan County, Utah, U.S.A.
Upon first glance, this specimen appears to be a chunk of nondescript brown quartzite rock with a few tiny traces of yellow coloring here and there. However, when one bathes it in shortwave UV light, one can easily see that a substantial portion of its surface area is covered with a thin layer of Uranopilite, a uranium sulfate mineral. Under UV, this thin layer glows a bright blue-green (it appears blue in the image). Close examination under normal light will show a slight yellow discoloration where the mineral coats the host. It is rather nondescript, as it shows no crystal form whatsoever and has a very dull luster. This is one of the best examples of a fluorescent mineral that I have seen, as the material is practically invisible under white light.