VANARSITE, PACKRATITE, MORRISONITE, AND GATEWAYITE: FOUR NEW MINERALS CONTAINING THE [As3+V124+,5+As65+O51] HETEROPOLYANION, A NOVEL POLYOKOMETALATE CLUSTER

摘要

Vanarsite (IMA2014-031), NaCa12(As3+V3.54+V8.55+As65+O51)(2).78H2O, packratite (IMA2014-059), Ca-11(As3+V24+V105+As65+O51)(2).83H(2)O, morrisonite (IMA2014-088), Ca-11(As3+V24+V105+As65+O51)(2).78H2O, and gatewayite (IMA2014-096), Ca-6(As3+V34+V95+As65+O51).31H(2)O, are four new minerals from the Packrat mine, Gateway district, Mesa County, Colorado, U.S.A. Crystals of all four new minerals are very dark blue to greenish-blue blades. They are found together on montroseite- and corvusite-bearing sandstone in association with pharmacolite. Vanarsite is monoclinic, P2(1)/c, a 25.8902(8), b 10.9468(3), c 28.2980(8) A, beta 102.252(1), V 7828.9(3) A(3), and Z = 2. Packratite is triclinic, P (1) over bar, a 18.0572(4), b 19.4126(4), c 24.0586(17) A, alpha 87.364(6), beta 86.266(6), gamma 79.267(6), V 8263.4(7) A(3), and Z = 2. Morrisonite is monoclinic, P2(1)/c, a 14.9566(18), b 48.208(6), c 23.836(3) A, beta 90.034(6), V 17187(4) A(3), and Z = 4. Gatewayite is monoclinic, P2(1), a 11.1850(4), b 16.8528(4), c 20.7146(15) A, beta 91.166(6), V 3903.9(3) A(3), and Z = 2. The structures of all four new minerals contain the novel polyoxometalate-like heteropolyanion, [As3+As65+V2+x4+V10x5+O51]((11+x)) (x = 0 to 1.5), which is new to science.