Jakub Plasil

Institute of Physics ASCR | FZU · Department of Structure Analysis

The new mineral scenicite (IMA2021-057), [(UO2)(H2O)2(SO4)]2·3H2O, was found in the Green Lizard, Giveaway-Simplot, Markey and Scenic mines, White Canyon district, San Juan County, Utah, USA, where it occurs as a secondary phase on granular quartz matrix in association with various combinations of deliensite, gypsum, natrozippeite, rietveldite and...

Michalskiite (IMA2019-162), Cu2+Mg3Fe3+3.33(VO4)6, is a new mineral found on specimens from the dump of the Lichtenberg open pit, Ronneburg uranium mining district, Thuringia, Germany. It is a secondary mineral occurring with arcanite, epsomite, hematite and syngenite on matrix consisting of fine-grained quartz, K-feldspar and mica. It forms striat...

Gurzhiite, ideally Al(UO2)(SO4)2F·10H2O, is a new uranyl sulfate mineral from the Bykogorskoe U deposit, Northern Caucasus, Russia. It occurs as fine-grained aggregates forming veinlets up to 50 cm long in cracks of the brecciated rock. Gurzhiite aggregates are composed of small bladed crystals up to 0.1 mm across. Associated minerals include khade...

Weathering of ore minerals proceeds through initial transient products to many crystalline secondary minerals. However, the initial products are usually poorly characterized or overlooked because of their extremely small particle size, poor crystallinity, and chemical variability. Here, we document the strength of the precession-assisted three-dime...

Re-investigation of the type material of beraunite from the Hrbek Mine, Svatá Dobrotivá, Czech Republic, proved the identity of beraunite and eleonorite. Based on this study, the mineral eleonorite was discredited, and the ideal formula of beraunite was redefined from Fe2+Fe53+(PO4)4(OH)5 ⋅ 6H2O to Fe63+(PO4)4O(OH)4 ⋅ 6H2O. Beraunite from Hrbek Min...

The Vorontsovskoe gold deposit (Northern Urals) is unique in both Russia and the world because of the diverse and original Tl–Hg–Mn–As–Sb–S mineralization. Based on the available literature and our data, we present a list of 210 minerals found at this deposit. Eight of them are new minerals discovered by the authors: vorontsovite, ferrovorontsovite...

The new mineral ferroberaunite, Fe2+Fe3+5(PO4)4(OH)5·6H2O (IMA 2021-36; symbol: Fbru), occurs in cavities of limonite iron ore from the Gravel Hill mine, Perranzabuloe, Cornwall, England, United Kingdom. Its flattened prismatic crystals up to 400 μm long are dark green to olive green, transparent to translucent, with a vitreous lustre, pearly on cl...

A synthetic analogue of the mineral natroboltwoodite was obtained unprecedently during a dissolution experiment with the mineral yttrialite-(Y), at a temperature of 200 °C, pressure ∼1.5 MPa, and strongly alkaline conditions. Natroboltwoodite formed along with analcime and aegirine. Single crystals of natroboltwoodite obtained allowed us to reveal...

Particularly interesting chemical variability in the U 4+ phosphate mineral vyacheslavite from Menzenschwand (Germany) has been discovered and investigated by means of electron-diffraction and micro-chemical methods. Suggested variability comprises namely the elevated contents of calcium and rare-earth elements (REEs). Based on the crystal structur...

The new mineral paramarkeyite (IMA2020–024), Ca2(UO2)(CO3)3·5H2O, was found in the Markey mine, San Juan County, Utah, USA, where it occurs as a secondary phase on gypsum-coated asphaltum in association with andersonite, calcite, gypsum and natromarkeyite. Paramarkeyite crystals are transparent, pale green-yellow, striated tablets, up to 0.11 mm ac...

In this work, the structures of chemically related uranyl-oxide minerals agrinierite and rameauite have been revisited and some corrections to the available structure data are provided. Both structures were found to be twinned. The two minerals are chemically similar, and though their structures differ considerably, their unit-cell metrics are simi...

Ferroberaunite IMA No. 2021-036 Chemical formula (ideal formula): Fe2+Fe3+5(PO4)4(OH)5⋅6H2O Mineral symbol: Fbru Type locality: Gravel Hill Mine, Perranzabuloe, Cornwall, England, United Kingdom Relationship to other minerals: The Fe2+ analogue of zincoberaunite Crystal system, Space group: Monoclinic: C2/c; structure determined Unit-cel...

This is a fnal paper in a series of publications devoted to the mineralogy of the Vorontsovskoe gold deposit in the Northern Urals. The article reports on oxygen compounds (oxyhalides, oxides, hydroxides, carbonates, sulfates, tungstates, phosphates, arsenates and silicates) of the Vorontsovskoe deposit, their chemical composition and, for selected...

Uranotungstite is an uranyl-tungstate mineral that was until recently only partially characterized with a formula originally given as (Fe2+,Ba,Pb)(UO2)2(WO4)(OH)4·12H2O and an unknown crystal structure. This mineral has been reinvestigated by electron microprobe analysis coupled with 3D electron diffraction. According to the electron microprobe dat...

The crystal structure of Tl 2.36 Sb 5.98 As 4.59 S 17 , the lead-free endmember of the chabournéite homeotypic group, from the Tl-As-Sb-rich gold deposit at Vorontsovskoye (the Urals, Russia) was determined and refined to R(obs) 0.099 for 9340 unique observed X-ray reflections. The triclinic unit-cell parameters determined from single-crystal data...

Auerbakhite (IMA 2020-047), MnTl2As2S5 , is a new sulfosalt from the Vorontsovskoe gold deposit, Sverdlovsk Ob-last', Northern Urals, Russia. The new mineral occurs in limestone breccias composed of calcite, dolomite, baryte, clinochlore, fluorapatite and quartz, and cemented by major realgar, orpiment and pyrite. Other minerals directly associatin...

The new sulfate mineral ferroefremovite, ideally (NH4)2Fe2+2(SO4)3, was discovered at the “Bocca Grande” fumarole, Solfatara di Pozzuoli, Flegrean Volcanic Complex, Naples Province, Campania, Italy. Associated minerals are adranosite, adranosite-(Fe), godovikovite, huizingite-(Al), mascagnite, and opal. Ferroefremovite forms cubic crystals up to 0....

Gungerite, TlAs5Sb4S13, is a new mineral from the Vorontsovskoye gold deposit in Northern Urals. It occurs in limestone breccias composed of calcite and dolomite, and cemented by orpiment, pyrite, realgar, stibnite, and minor baryte and quartz. It belongs to the latest phases among sulfosalts (chiefly Tl–As–Sb ones) present in the ore. The empirica...

Nitscheite (IMA2020-078), (NH4)2[(UO2)2(SO4)3(H2O)2]·3H2O, is a new mineral species from the Green Lizard mine, Red Canyon, San Juan County, Utah, U.S.A. It is a secondary phase found in association with chinleite-(Y), gypsum, pyrite, and Co-rich rietveldite. Nitscheite occurs in subparallel and divergent intergrowths of yellow prisms, up to about...

This paper continues a series of publications devoted to the mineralogy of the Vorontsovskoe gold deposit in the Northern Urals (Kasatkin et al., 2020, 2021). The article reports on sulfosalts of the deposit, their chemical compositions, as well as unit-cell parameters, optical properties and Raman spectra of some minerals. For eight new mineral sp...

Dobšináite, ideally Ca 2 Ca(AsO 4) 2 ·2H 2 O, is a new supergene mineral from the Dobšiná deposit, Slovak Republic, associated with phaunouxite, picropharmacolite, erythrite-hörnesite, gypsum and aragonite. It forms white to pink clusters or polycrystalline aggregates up to 1-4 mm in size consisting of densely intergrown, slightly rounded thin tabu...

Uranyl carbonates are one of the largest groups of secondary uranium(VI)-bearing natural phases being represented by 40 minerals approved by the International Mineralogical Association, overtaken only by uranyl phosphates and uranyl sulfates. Uranyl carbonate phases form during the direct alteration of primary U ores on contact with groundwaters en...

The new mineral uranoclite (IMA2020-074), (UO2)2(OH)2Cl2(H2O)4, was found in the Blue Lizard mine, San Juan County, Utah, USA, where it occurs as tightly intergrown aggregates of irregular yellow crystals in a secondary assemblage with gypsum. The streak is very pale yellow and the fluorescence is bright green-white under 405 nm ultraviolet light....

Revisiting the structure of uranyl arsenate mineral hügelite provided some corrections to the available structural data. The previous twinning model (by reticular merohedry) in hügelite has been corrected. Twinning of the monoclinic unit cell [ a = 7.0189 (7) Å, b = 17.1374 (10) Å, c = 8.1310 (10) Å and β = 108.904 (10)°], which can be expressed as...

The paper continues a series of publications devoted to the mineralogy of the Vorontsovskoe gold deposit in the Northern Urals (Kasatkin et al., 2020). The paper reports on native elements, sulfdes, arsenides and tellurides discovered at the deposit, their chemical compositions, as well as unitcell parameters and optical properties of some minerals...

The new mineral grimmite, NiCo2S4, was found in siderite–sphalerite gangue at the dump of shaft no. 9, one of the mines in the abandoned Příbram uranium and base-metal district, central Bohemia, Czech Republic. The new mineral occurs as rare idiomorphic to hypidiomorphic grains up to 200 µm × 70 µm in size or veinlet aggregates. In reflected light,...

Krupičkaite, ideally Cu6[AsO3(OH)]6·8H2O, is a new supergene mineral from the Rovnost I shaft in Jáchymov, Czech Republic. It forms aggregates of pale greenish-blue color and grows along with supergene minerals crystallizing on the strongly altered relics of massive tennantite, Bi-rich tennantite, galena, chalcopyrite, bornite, and chalcocite with...

The new mineral hrabákite (IMA2020-034) was found in siderite–sphalerite gangue with minor dolomite–ankerite at the dump of shaft No. 9, one of the mines in the abandoned Příbram uranium and base-metal district, central Bohemia, Czech Republic. Hrabákite is associated with Pb-rich tučekite, Hg-rich silver, stephanite, nickeline, millerite, gersdorf...

Kaatialaite mineral Fe[AsO 2 (OH) 2 ]5H 2 O from Já chymov, Czech Republic forms white aggregates of needle-shaped crystals with micrometric size. Its structure at ambient temperature has already been reported but hydrogen atoms could not be identified from single-crystal X-ray diffraction. An analysis using 3D electron diffraction at low temperatu...

Seaborgite (IMA2019-087), LiNa6K2(UO2)(SO4)5(SO3OH)(H2O), is a new mineral species from the Blue Lizard mine, Red Canyon, San Juan County, Utah, U.S.A. It is a secondary phase found on gypsum in association with copiapite, ferrinatrite, ivsite, metavoltine, and römerite. Seaborgite occurs in sprays of light-yellow, long flattened prisms or blades,...

Panskyite, Pd 9 Ag 2 Pb 2 S 4 , is a new mineral (IMA2020–039) discovered in the platinum-group element mineralisation of the Southern Kievey ore occurrence of the Fedorova–Pana layered intrusion, Kola Peninsula, Russia. It forms tiny anhedral grains (of 0.5 to 10 μm in size) in the interstices of rock-forming silicates, often forming tiny inclusio...

This work is the frst paper in a series of publications dedicated to mineralogy of the Vorontsovskoe gold deposit in the Northern Urals. The deposit is unique for both Russia and world with regard to the diversity and originality of Tl–Hg–Mn–As–Sb–S mineralization. Based on available literature and our data, we compiled an exhaustive list of 209 mi...

A rare supergene uranyl phosphate mineral, phurcalite, was found on a few specimens originating from the dump material of the Eduard shaft, the Jáchymov ore district, Czech Republic. Phurcalite forms yellow to yellowish-orange perfect prismatic crystals, reaching up to 3 - 4 mm in cavities of vuggy quartz-dominated gangue. Phurcalite was found in t...

The crystal structure of the rare supergene Pb2+-containing uranyl-oxide mineral wölsendorfite has been revisited employing the single-crystal X-ray diffraction. The new structure refinement provided deeper insight into the complex structure of this mineral, revealing additional H2O sites in the interlayer complex and confirming the entrance of the...

The new sulfosalt chukotkaite, ideally AgPb7Sb5S15, was discovered in the valley of the Levyi Vulvyveem river, Amguema river basin, Iultin District, Eastern Chukotka, Chukotka Autonomous Okrug, North-Eastern region, Russia. The new mineral forms anhedral grains up to 0.4 × 0.5 mm intergrown with pyrrhotite, sphalerite, galena, stannite, quartz, and...

The new mineral percleveite-(La) (IMA2019–037), ideally La 2 Si 2 O 7 , was found in polymineralic nodules of the Mochalin Log REE deposit, Chelyabinsk Oblast, South Urals, Russia. It is associated with allanite-(Ce), allanite-(La), bastnäsite-(Ce), bastnäsite-(La), ferriallanite-(Ce), ferriallanite-(La), ferriperbøeite-(Ce), ferriperbøeite-(La), f...

The underground spaces of the former mines in Jáchymov, Czech Republic and Rotgülden, Austria house diverse assemblages of secondary minerals, mostly arsenates. The formation conditions and processes involved with the secondary minerals were deciphered using field observations, sampling of both solids and co-existing aqueous solutions, calorimetric...

The new mineral pošepnýite was found in the mine dump of the shaft No. 16 Háje, one of the mines in the Příbram uranium and base-metal district, central Bohemia, Czech Republic. Pošepnýite is associated with příbramite, dzhar-kenite, ferroselite, hakite-(Hg), tetrahedrite-(Zn), antimonselite and uraninite in a calcite-dominant gangue. The new miner...

Monteneroite (IMA2020–028), Cu2+Mn2+2(AsO4)2·8H2O, is a new vivianite–structure mineral from the Monte Nero mine, Rocchetta di Vara, La Spezia, Liguria, Italy. It is a secondary mineral that crystallized from As–, Cu– and Mn–rich fluids and it is associated with braunite, copper, cuprite, rhodochrosite and strashimirite. Monteneroite occurs as ligh...

The research involving the crystal structures and properties of uranyl carbonate minerals is essential in actinide environmental chemistry due to the fundamental role played by these minerals in the migration of actinides from uranium deposits and nuclear waste repositories and in the investigation of accidental site contaminations. In this work, t...

The new minerals natromarkeyite, Na 2 Ca 8 (UO 2) 4 (CO 3) 13 (H 2 O) 24 ⋅3H 2 O (IMA2018-152) and pseudomarkeyite, Ca 8 (UO 2) 4 (CO 3) 12 (H 2 O) 18 ⋅3H 2 O (IMA2018-114) were found in the Markey mine, San Juan County, Utah, USA, where they occur as secondary phases on asphaltum. Natromarkeyite properties are: untwinned blades and tablets to 0.2...

Fulbrightite (IMA2019-032), Ca(VO) 2 (AsO 4) 2 Á4H 2 O, is a new mineral from the Packrat mine, near Gateway, Mesa County, Colorado, USA, and from the Rovnost mine, Jáchymov, Czech Republic. It is a low-temperature secondary phase. The mineral most typically occurs in shades of light green and forms rosettes of roughly square (pseudotetragonal) pla...

The determination of the full crystal structure of the uranyl sulfate mineral uranopilite, (UO2)6(SO4)O2(OH)6.14H2O, including the positions of the hydrogen atoms within the corresponding unit cell, has not been feasible to date due to the poor quality of its X-ray diffraction pattern. In this paper, the complete crystal structure of uranopilite is...

The determination of the full crystal structure of the uranyl sulfate mineral uranopilite, (UO2 )6 (SO4)O2(OH)6·14 H2O, including the positions of the hydrogen atoms within the corresponding unit cell, has not been feasible up to date due to the poor quality of its X-ray diffraction pattern. In this paper, the complete crystal structure of uranopil...

IMA no. 2020-028 Monteneroite Cu2+Mn2+2(AsO4)2·8H2O Monte Nero mine, Rocchetta di Vara, La Spezia, Liguria, Italy (44°14'48"N, 9°45'27" E) Anthony R. Kampf*, Jakub Plášil, Barbara P. Nash, Marco E. Ciriotti, Fabrizio Castellaro, and Luigi Chiappino *E-mail: akampf@nhm.org Structurally related to vivianite Monoclinic: C2/m; structure determined a =...

The new minerals natromarkeyite (IMA2018-152), Na 2 Ca 8 (UO 2) 4 (CO 3) 13 (H 2 O) 24 ·3H 2 O, and pseudomarkeyite (IMA2018-114), Ca 8 (UO 2) 4 (CO 3) 12 (H 2 O) 18 ·3H 2 O, were found in the Markey mine, San Juan County, Utah, USA, where they occur as secondary phases on asphaltum. Natromarkeyite properties: untwinned blades and tablets to 0.2 mm...

We have undertaken a study of the arsenate mineral chongite from the second world occurrence, which is Jáchymov (Czech Republic). Chongite occurs as colourless to white crystalline spherical and hemispherical aggregates up to 0.3 mm across composed of rich crusts on strongly weathered fragments of rocks and gangue. The chemical composition of chong...

Niasite (IMA2019-105) and johanngeorgenstadtite (IMA2019-122) are Ni4.52+(AsO4)3 dimorphs from Johanngeorgenstadt, Saxony, Germany. The two new minerals occur in association with one another and with aerugite, bunsenite, quartz, rooseveltite and xanthiosite. This mineral assemblage is apparently secondary in origin and most likely formed from the b...

Luboržákite, ideally Mn 2 AsSbS 5 , is a new mineral from the Vorontsovskoe gold deposit, Northern Urals, Russia. It forms long-prismatic crystals up to 70 × 20 μm and anhedral grains of the same size embedded in the matrix of Mn-bearing dolomite and Mn-bearing calcite. Associated minerals include pyrite, orpiment, realgar, stibnite, aktashite, ala...

The new mineral pseudomeisserite-(NH4) (IMA2018-166), (NH4,K)2Na4[(UO2)2(SO4)5]·4H2O, was found in the Blue Lizard mine, San Juan County, Utah, USA, where it occurs as light yellow prisms in a secondary assemblage with belakovskiite, blödite, changoite, ferrinatrite, gypsum, ivsite, metavoltine, tamarugite. The streak is very pale yellow and the fl...

The crystal structure of phurcalite, Ca 2 [(UO 2 ) 3 O 2 (PO 4 ) 2 ]·7H 2 O, orthorhombic, a = 17.3785 (9) Å, b = 15.9864 (8) Å, c = 13.5477 (10) Å, V = 3763.8 (4) Å ³ , space group Pbca , Z = 8 has been refined from single-crystal XRD data to R = 0.042 for 3182 unique [ I > 3σ( I )] reflections and the hydrogen-bonding scheme has been refined by t...

The new mineral fluorapophyllite-(NH4), ideally NH4Ca4(Si8O20)F•8H2O, was found at the Vechec andesite quarry located near Vechec village, Vranov nad Topľou Co., Prešov Region, Slovak Republic. It occurs in cavities of quartz-illite-saponite-tobelite xenolith embedded in pyroxene andesite. Fluorapophyllite-(NH4) is associated with calcite, tridymit...

The phases pushcharovskite, geminite and liroconite were synthesized or acquired and characterized by powder X-ray diffraction, infrared spectroscopy, electron microprobe analysis, thermogravimetric analysis and optical emission spectrometry, as needed. Their thermodynamic properties were determined by a combination of acid-solution calorimetry and...