2017
Plavnoite, a new K-Mn member of the zippeite group from Jachymov, Czech Republic
PLÁŠIL, Jakub, Pavel ŠKACHA, Jiří SEJKORA, Antony KAMPF, Radek ŠKODA et. al.Základní údaje
Originální název
Plavnoite, a new K-Mn member of the zippeite group from Jachymov, Czech Republic
Autoři
PLÁŠIL, Jakub (203 Česká republika), Pavel ŠKACHA (203 Česká republika), Jiří SEJKORA (203 Česká republika), Antony KAMPF (840 Spojené státy), Radek ŠKODA (203 Česká republika, garant, domácí), Jiří ČEJKA (203 Česká republika), Jan HLOUŠEK (203 Česká republika), Anatoly KASATKIN (643 Rusko), Radim PAVLÍČEK (203 Česká republika) a Karel BABKA (203 Česká republika)
Vydání
European Journal of Mineralogy, STUTTGART, E SCHWEIZERBARTSCHE VERLAGSBUCHHANDLUNG, SCIENCE PUBLISHERS, 2017, 0935-1221
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10504 Mineralogy
Stát vydavatele
Německo
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 1.190
Kód RIV
RIV/00216224:14310/17:00100327
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000396823700010
Klíčová slova anglicky
plavnoite; uranyl sulfate hydrate; new mineral; zippeite group; crystal structure; chemical composition
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 10. 4. 2018 16:52, Ing. Nicole Zrilić
Anotace
V originále
The new mineral plavnoite (IMA2015-059), ideally K0.8Mn0.6[(UO2)(2)O-2(SO4)]center dot 3.5H(2)O, is a member of the zippeite group. It was found in the Plavno mine, in the eastern part of the Jachymov ore district, Western Bohemia, Czech Republic, where it occurs as a supergene alteration phase formed by hydration-oxidation weathering of uraninite in hydrothermal U-veins. It was found to be associated with marecottite, magnesiozippeite, blatonite and gypsum. The mineral occurs as reddish to reddish-orange thin blades, elongated on [0 0 1] and flattened on {0 1 0}, which are intergrown in globular aggregates up to 0.5 mm across. Crystals are transparent with a vitreous to silky lustre. The streak is pale orange. The mineral is non-fluorescent under both long- and short-wave ultraviolet (UV) radiation. The Mohs hardness is about 2. Crystals are brittle with perfect {0 1 0} cleavage and uneven fracture. The density calculated from the empirical formula is 4.926 g cm(-3). Optically, plavnoite is biaxial (+), with alpha = 1.740(5), beta = 1.770(5), gamma = 1.850(5) (measured in white light). The measured 2V is 64.6(4)degrees; the calculated 2V is 65.3 degrees. Dispersion could not be observed; no pleochroism was observed. Electron-microprobe analyses yielded the empirical formula (based on 2 U atoms per formula unit,apfu) K-0.77(Mn0.51Zn0.04Ni0.03Mg0.02)(Sigma 0.60)[(UO2)(2)O-1.08(OH)(0.92)(SO4)(0.96)(SiO4)(0.24)](H2O)(3.50). Plavnoite is monoclinic, C2/c, a = 8.6254 (16), b = 14.258(3), c = 17.703(4) angstrom, beta = 104.052(18)degrees, V = 2122.0(8) angstrom(3) and Z = 8. The structure (R-1 = 4.99% for 989 reflections with 1 > 3 sigma[I]) contains UO7 pentagonal bipyramids and SO4 tetrahedra forming sheets of the well-known zippeite topology. The interlayer region contains infinite zig-zag chains of corner-sharing Mn2+phi(6) octahedra (phi=O, H2O) with K-centred polyhedra. The K atom sits at the partially occupied, mixed K/O site, the non-shared corner of the Mn2 octahedron. The mineral is named after the type locality - the Plavno mine.
Návaznosti
MUNI/A/1316/2015, interní kód MU |
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