Klaprothite, péligotite and ottohahnite, three new minerals with bidentate UO₇–SO₄linkages from the Blue Lizard mine, San Juan County, Utah, USA

Abstract

The new minerals klaprothite (IMA2015-087), Na6(UO2)(SO4)4(H2O)4, péligotite (IMA2015-088), Na6(UO2)(SO4)4(H2O)4 and ottohahnite (IMA2015-098),Na6(UO2)2(SO4)5(H2O)7·1.5H2O, were found in the Blue Lizard mine, San Juan County, Utah, USA, where they occur together as secondary phases. All three minerals occur as yellowish-green to greenish-yellow crystals, are brittle with irregular fracture, have Mohs hardness of ∼2½ and exhibit bright bluish-green fluorescence, and all are easily soluble in room temperature H2O. Only klaprothite exhibits cleavage; perfect on {100} and {001}. Quantitative energydispersive spectroscopy analyses yielded the empirical formulas Na6.01(U1.03O2)(S0.993O4)4(H2O)4, Na5.82(U1.02O2)(S1.003O4)4(H2O)4 and Na5.88(U0.99O2)2(S1.008O4)5(H2O)8.5 for klaprothite, péligotite and ottohahnite, respectively. Their Raman spectra exhibit similar features. Klaprothite is monoclinic, P21/c, a = 9.8271(4), b = 9.7452(3), c = 20.8725(15) Å, β = 98.743(7)°, V = 1975.66(17)Å3 and Z = 4. Péligotite is triclinic, P1̄, a = 9.81511(18), b = 9.9575(2), c = 10.6289(8) Å, α = 88.680(6)°, β = 73.990(5)°, γ = 89.205(6)°, V = 998.22(8) Å3 and Z =2. Ottohahnite is triclinic, P1̄, a = 9.97562(19), b = 11.6741(2), c = 14.2903(10) Å, α = 113.518(8)°, β = 104.282(7)°, γ = 91.400(6)°, V = 1464.59(14) Å3 and Z = 2. The structures of klaprothite(R1 = 2.22%) and péligotite (R1 = 2.28%) both contain [(UO2)(SO4)4]6– clusters in which one SO4 group has a bidentate linkage with the UO7 polyhedron; Na–O polyhedra linkclusters into thick heteropolyhedral layers and link layers into frameworks; the structures differ in the configuration of Na–O polyhedra that link the layers. The structure of ottohahnite (R1 = 2.65%) contains [(UO2)4(SO4)10]12–clusters in which each UO7 polyhedron has a bidentate linkage with one SO4 group; Na–O polyhedra link clusters into a thin heteropolyhedral slice and also link the slices into a framework. The minerals are named for Martin Heinrich Klaproth (1743–1817), Eugène-MelchiorPéligot (1811–1890) and Otto Hahn (1879–1968).

Pseudomeisserite-(NH4), a new mineral with a novel uranyl-sulfate linkage from the Blue Lizard mine, San Juan County, Utah, USA

“…The U2 bipyramid is surrounded by four SO 4 groups, three of which (centred by S1, S2 and S3) share single O eq corners and one of which (centred by S4) shares two equatorial O atoms, a polyhedral edge. Such a bidentate linkage between a UO 7 pentagonal bipyramid and a SO 4 tetrahedron has been previously reported in the Na-uranyl-sulfate minerals klaprothite, péligotite and ottohahnite (Kampf et al , 2017b) and lussierite (Kampf et al ., 2019; Fig. 5 a ), all of which occur at the Blue Lizard mine.…”

Markeyite, a new calcium uranyl carbonate mineral from the Markey mine, San Juan County, Utah, USA

“…The Markey mine is located ~1 km southwest of the Blue Lizard mine, on the east-facing side of Red Canyon, ~72 km west of the town of Blanding, Utah, and ~22 km southeast of Good Hope Bay on Lake Powell. The geology of the Markey Mine is quite similar to that of the Blue Lizard mine (Chenoweth, 1993; Kampf et al , 2016), although the secondary mineralogy of the Markey mine is notably richer in carbonate phases. The information following is taken largely from Chenoweth (1993).…”

Natromarkeyite and pseudomarkeyite, two new calcium uranyl carbonate minerals from the Markey mine, San Juan County, Utah, USA

“…The Markey mine is located ∼1 km southwest of the Blue Lizard mine, on the east-facing side of Red Canyon, ∼72 km west of the town of Blanding, Utah, and ∼22 km southeast of Good Hope Bay on Lake Powell. The geology of the Markey Mine is quite similar to that of the Blue Lizard mine (Chenoweth, 1993;Kampf, et al, 2017), although the secondary mineralogy of the Markey mine is notably richer in carbonate phases. Underground gas measurements collected in 2016 using a hand-held Crowcon Gasman CO 2 monitor showed consistently elevated CO 2 levels at the Markey mine, averaging ∼1000 ppm CO 2 with a maximum recorded value of 1600 ppm CO 2 , levels considerably higher than at the nearby Blue Lizard mine where carbonate mineral species are less abundant.…”