New Utah Minerals: Utahite, Juabite, and Blatonite
By Carl Ege
Utahite is a hydrated copper-zinc-tellurate hydroxide found on the dump of the Centennial Eureka mine in the Tintic mining district in Juab County. The mineral is found isolated or in groups as elongate crystals in small vugs with drusy quartz. Individual crystals are up to 0.3 mm long, prismatic, and are subhedral to euhedral. Utahite is pale blue in individual crystals or blue-green in aggregates. Utahite has a vitreous to pearly luster and a pale blue streak. X-ray studies reveal a triclinic symmetry. Utahite is nonfluorescent under ultraviolet light and is brittle with an uneven fracture. The mineral has a hardness of 4-5 and a density of 5.34 g/cm3.
Utahite is found in association with cesbronite and other Cu-Zn-Te-bearing secondary minerals on quartz. Utahite is named for the state where the Centennial Eureka mine is located.
Juabite is a copper-tellurate-arsenate hydrate found on the dump of the Centennial Eureka mine in the Tintic mining district in Juab County. The mineral is found isolated or in groups as elongate crystals on drusy quartz. Cystalline masses average 0.2 – 0.3 mm in size and are subhedral to euhedral. Juabite is emerald green, has a vitreous to adamantine luster, and a pale green streak. Individual juabite crystals are transparent, but juabite masses are translucent. X-ray study results reveal a triclinic symmetry. Juabite is nonfluorescent under ultraviolet light and is brittle with an uneven to subconchoidal fracture. The mineral has a hardness of 3-4 and a density of 4.59g/cm3.
Juabite is found in association with enargite, beudantite, and an unidentified lead-rich form of arsenobismite. Juabite is named for the county within the state of Utah where the Centennial Eureka mine is located.
Blatonite is a uranyl carbonate monohydrate found in gypsum seams within the Triassic Shinarump Conglomerate at the Jomac mine, San Juan County. The mineral occurs as subparallel fibers up to 1 mm long and 0.1 mm wide. Blatonite is canary-yellow, has a white streak, silky luster, and is translucent. X-ray study reveals a hexagonal or trigonal symmetry. Blatonite fluoresces strongly under ultraviolet light and is flexible with an uneven fracture. The mineral has a hardness of 2-3 and a density of 4.02 g/cm3.
Blatonite is found in association with boltwoodite, coconinoite, metazeunerite, rutherfordine, azurite, malachite, carbonate-cyanotrichite, brochantite, and smithsonite. Blatonite is named for N. Blaton of the University of Leuven, Belgium.
Roberts, A.C., Gault, R.A., Jensen, M.C., Criddle, A.J., and Moffatt, E.A., 1997, Juabite, a new mineral species from the Centennial Eureka mine, Juab County, Utah: Mineralogical Magazine, v. 61(1), p.139-144.
Roberts, A.C., Stirling, J.A.R., Criddle, A.J., Jensen, M.C., Moffatt, E.A., and Wilson, W.E., 1997, Utahite, a new mineral and associated copper tellurates from the Centennial Eureka mine, Tintic District, Juab County, Utah: Mineralogical Record, v. 28, p. 175-179.
Vochten, R., and Deliens M., 1998, Blatonite, a new uranyl carbonate monohydrate from San Juan County, Utah: Canadian Mineralogist, v. 36, p. 1077-1081.
Survey Notes, v. 32 no. 1, January 2000