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Papers by Petr Ondruš
Journal of Geosciences, 1997
Introduction Torbern Olof Bergman was born in Katrineberg, Sweden, the son of Barthold Bergman, s... more Introduction Torbern Olof Bergman was born in Katrineberg, Sweden, the son of Barthold Bergman, sheriff on the royal estate at Katrineberg. Bergman studied mathematics, philosophy, physics and astronomy at the University of Uppsala, graduating in 1756. He later joined the faculty of the University, teaching physics and mathematics, and succeeded to Wallerius chair as Professor of chemistry in 1767. He developed a growing interest in chemistry, mineralogy and crystallography when demonstrated how the stacking of rhombohedral units could produce a scalenohedron. (Haüy later proposed the same thing but denied having known on Bergman's theories.) [217]. Jáchymov is type locality for 17 secondary minerals. Ten of these minerals were named after persons, including some prominent mineralogists of the 19th century. Interesting biographical data on these personalities were assembled during work on the projects of study of the secondary minerals in the Jáchymov ore district (Grant Agency ...
Journal of Geosciences, 2003
Journal of Geosciences, 1997
Journal of Geosciences, 2003
New naturally occuring mineral phases from Krasno-Horni Slavkov area, western Bohemia, Czech Repu... more New naturally occuring mineral phases from Krasno-Horni Slavkov area, western Bohemia, Czech Republic
American Mineralogist, 1999
Parascorodite, a new mineral from Kaňk near Kutná Hora, Central Bohemia, Czech Republic, forms ea... more Parascorodite, a new mineral from Kaňk near Kutná Hora, Central Bohemia, Czech Republic, forms earthy white to white-yellow aggregates associated with scorodite, pitticite, bukovskýite, kaňkite, zýkaite, gypsum, and jarosite, wet chemical analysis gave (in wt%): As 2 O 5 44.45, P 2 O 5 0.84, SO 3 1.53, Fe 2 O 3 34.55, Al 2 O 3 0.17, H 2 O 17.81, totaling 99.95. The simplified chemical formula is FeAsO 4 •2H 2 O. Selected area electron diffraction suggests hexagonal or trigonal symmetry. The extinction symbol is P-c-. Powder X-ray diffraction yielded unit-cell parameters a = 8.9327(5) Å, c = 9.9391(8) Å, V = 686.83 (8) Å 3 , Z = 6. Densities (measured and calculated, respectively) are D m = 3.213(3) g/cm 3 and D x = 3.212 g/cm 3. SEM and TEM images showed that basal sections of parascorodite are hexagonal in shape; thicker prismatic crystals were also observed. Crystal size varies between 0.1 to 0.5 µm. The strongest lines in the X-ray powder diffraction pattern are [d[I](hkl)]: 4.184(44)(012), 4.076(100)(111), 3.053(67)(202), 2.806(68)(211), 2.661(59)(113), 2.520(54)(212), 2.2891(44)(032). Refractive indexes could not have been measured due to extremely small crystallite size, n-(calc) = 1.797. The TG curve shows two weight losses: at 20-150 °C (2.1 wt%, absorbed water) and at 150-620 °C (15.5 wt%, molecular water), respectively. They correspond to the endothermic peaks on the DTA curve at 120 and 260 °C. Strong exothermic reaction observed at 585 °C reflects formation of the phase FeAsO 4. Infrared absorption spectra of parascorodite are close to those of scorodite.
Journal of Geosciences, 2003
This contribution provides a brief review of geology of the Kruné hory Mts. (Erzgebirge) and spec... more This contribution provides a brief review of geology of the Kruné hory Mts. (Erzgebirge) and specifically of the Jáchymov (Joachimsthal) deposit. Main types of rocks in the Jáchymov ore district and the role of tectonic processes are described. The position of the ore district is defined much like its tectonic borders. Geological factors controlling the mineralization (especially the so-called five-element mineralization) are summarized. Hydrothermal veins are divided into Morning and Midnight veins according to the classical historical speak of miners, and all vein clusters are listed. Vein hydrothermal five-element mineralization is chronologically divided into separate mineralization stages and their age is estimated.
Journal of GEOsciences, 2012
This paper presents results of study of supergene minerals occuring at the Huber stock and Schnöd... more This paper presents results of study of supergene minerals occuring at the Huber stock and Schnöd stock in the Krásno Sn-W ore district near Horní Slavkov (Slavkovský les area, Czech Republic). The mineralogical research is based on X-ray powder diffraction, electron microprobe analyses, optical and electron microscopy. The paper includes encyclopaedia-type presentation of the identified mineral species. The role of late hydrothermal, supergene, sub-recent and recent processes in the formation of minerals and their associations is discussed.
![Research paper thumbnail of Description and crystal structure of vajdakite, [(Mo 6+ O 2 ) 2 (H 2 O) 2 As 3+ 2 O 5 ]· H 2 O—A new mineral from Jáchymov, Czech Republic](https://attachments.academia-assets.com/96933835/thumbnails/1.jpg)
](American Mineralogist, 2002
American Mineralogist, 2003
Mineralogical Magazine, 2014
Hloušekite, (Ni,Co)Cu4(AsO4)2(AsO3OH)2(H2O)9, is a new supergene arsenate mineral from the Geiste... more Hloušekite, (Ni,Co)Cu4(AsO4)2(AsO3OH)2(H2O)9, is a new supergene arsenate mineral from the Geister vein (Rovnost mine), Jáchymov (St Joachimsthal), Western Bohemia, Czech Republic. It was found along with veselovský ite, pradetite, lavendulan, arsenolite, babánekite and gypsum on the surface of strongly altered ore fragments containing dominant tennantite and chalcopyrite. Hloušekite forms thin, lath-like crystals, locally elongated reaching up to 3 mm across. It is transparent, has a pale green colour with vitreous lustre, has a greyish-white streak and it is very brittle with an uneven fracture. It does not fluoresce under shortwave or longwave ultraviolet radiation. Cleavage on {010} is perfect; the Mohs hardness is 2–3. The calculated density is 3.295 g cm–3. Hloušekite is optically biaxial with α’ = 1.653(2) and γ’ = 1.73. The estimated optical orientation is γ’ vs. elongation (c) = 14(1)°. In larger grains it is weakly to moderately pleochroic (α = colourless, γ = pale green t...
Journal of GEOsciences, 2012
This paper presents the existing and newly obtained information on supergene minerals of the Horn... more This paper presents the existing and newly obtained information on supergene minerals of the Horní Slavkov uranium ore district. Mineralogical studies confirmed occurrences of the following minerals:
Journal of GEOsciences, 2012
The present detailed research is focused on minerals of phosphate accumulations collected in the ... more The present detailed research is focused on minerals of phosphate accumulations collected in the Huber open pit and at the 5 th level of the Huber shaft, Krásno ore district, Slavkovský les area, Czech Republic. The following minerals have been identified at the studied localities:
Journal of GEOsciences, 2012
Detailed mineralogical study focused on two deposits located on slopes of the Vysoký Kámen hill n... more Detailed mineralogical study focused on two deposits located on slopes of the Vysoký Kámen hill near Krásno in the proximity of the town of Horní Slavkov in Czech Republic. The open pit exploiting industrial feldspar material (mainly feldspathites and aplitic granites) offerred new finds of minerals in the Slavkovský les. The following minerals were identified: autunite, bertrandite, beryl, goethite, hematite, koechlinite, kolbeckite, meta-autunite, powellite and scheelite. In the nearby abandoned greisen deposit a phosphate mineral association was observed consisting of cacoxenite, leucophosphite, vivianite, wavellite and minerals of the chalcosiderite-turquoise and strengite-variscite series. In addition to them dickite and goethite were identified. The genesis of these mineral associations is discussed.
Neues Jahrbuch für Mineralogie - Abhandlungen, 2010
ABSTRACT Veselovskýite, (Zn,Cu,Co)Cu4(AsO4)2(AsO3OH)2 · 9H2O, is a new supergene mineral from the... more ABSTRACT Veselovskýite, (Zn,Cu,Co)Cu4(AsO4)2(AsO3OH)2 · 9H2O, is a new supergene mineral from the Geister vein, Mine Rovnost at the Jáchymov ore district (St. Joachimsthal), Czech Republic, commonly associated with strashimirite and blue amorphous Cu arsenate. It forms aggregates, up to 8 × 5 × 1 mm in size, consisting of lath-like to thin-tabular crystals, up to 1 mm long, commonly forming complicated intergrowths, no twinning was observed. Veselovskýite is translucent (aggregates) to transparent (crystals), colourless to greyish white (with a slight greenish tint). It has a greyish white streak with a greenish tint, a vitreous luster, does not fluoresce under both short- and long-wave ultraviolet light. Cleavage on {001} is perfect, Mohs hardness is ∼2-3, and veselovskýite is very brittle with an irregular fracture and calculated density 3.28 g/cm3. Veselovskýite is biaxial positive, the indices of refraction are nx´ 1.645(3), ny´ 1.68(1), nz´ ∼1.72, 2V(calc) approximative 88°, it is strongly pleochroic (nx = greenish, ny = pale green, nz = green), and the optical orientation is as follows: nx´ versus elongation (c) = 15(1)°. Veselovskýite is triclinic, space group P-1, a 6.4022(4), b 8.0118(4), c 10.3665(4) Å, α 85.491(3)°, β 79.377(4)°, γ 84.704(5)°, V 519.34(4) Å3, Z = 1, a:b:c = 0.7991:1:1.2939. The eight strongest lines in the X-ray powder diffraction pattern are as follows: d (Å), I, (hkl): 10.185, 100 (001), 7.974, 12 (010), 3.987, 13 (020), 3.637, 15 (0-21), 3.395, 37 (003), 3.238, 15 (022), 2.910, 12 (202), 2.668, 16 (023). The chemical analyses by electron microprobe yielded MgO 0.05, CaO 0.04, MnO 0.22, NiO 0.30, CoO 0.96, CuO 32.98, ZnO 3.39, Al2O3 0.24, P2O5,As2O5 43.16, H2O 17.90, total (100.00) wt.%. The resulting empirical formula on the basis of 25 (O, OH, H2O) anions is (Zn0.43Cu0.24Co0.13Al0.05Ni0.04Mn0.03Mg0.01Ca0.01)Σ0.94 Cu4.00 [(AsO4)1.92(PO4)0.11(AsO3OH)1.92] · 9.20H2O. The ideal end-member formula ZnCu4[(AsO4)2(AsO3OH)2] · 9H2O requires ZnO 7.83, CuO 30.61, As2O5 44.22, H2O 17.34, total 100.00 wt.%. Veselovskýite is isostructural with lindackerite and represents Zn-dominant analogue of lindackerite and pradetite. The name veselovskýite is in honor of František Veselovský (*1948), an outstanding Czech mineralogist, who described several new minerals from the Jáchymov ore district.
Mineralogy and Petrology, 2011
The new mineral agricolaite, a potassium uranyl carbonate with ideal formula K 4 (UO 2)(CO 3) 3 ,... more The new mineral agricolaite, a potassium uranyl carbonate with ideal formula K 4 (UO 2)(CO 3) 3 , occurs in vugs of ankerite gangue in gneisses in the abandoned Giftkiesstollen adit at Jáchymov, Czech Republic. The name is after Georgius Agricola (1494-1555), German scholar and scientist. Agricolaite occurs as isolated equant irregular translucent grains to 0.3 mm with yellow color, pale yellow streak, and vitreous luster. It is brittle with uneven fracture and displays neither cleavage nor parting. Agricolaite is non-fluorescent. Mohs hardness is~4. It is associated with aragonite, brochantite, posnjakite, malachite, rutherfordine, and "pseudo-voglite". Experimental density is higher than 3.3 g.cm −3 , Dcalc is 3.531 g.cm −3. The mineral is monoclinic, space group C2/c, with a 10.2380(2), b 9.1930(2), c 12.2110(3) Å, β 95.108(2)°, V 1144.71(4) Å 3 , Z=4. The strongest lines in the powder Xray diffraction pattern are d(I)(hkl): 6.061(55)(002), 5.087 (57)(200), 3.740(100)(202), 3.393(43)(113), 2.281(52) (402). Average composition based on ten electron microprobe analyses corresponds to (in wt.%) UO 3 48.53, K 2 O 31.49, CO 2 (calc) 22.04 which gives the empirical formula K 3.98 (UO 2) 1.01 (CO 3) 3.00. The crystal structure was solved from single-crystal X-ray diffraction data and refined to R 1 =0.0184 on the basis of the 1,308 unique reflections with F o >4σF o. The structure of agricolaite is identical to that of synthetic K 4 (UO 2)(CO 3) 3 and consists of separate UO 2 (CO 3) 3 groups organized into layers parallel to (100) and two crystallographically non-equivalent sites occupied by K + cations. Both the mineral and its name were approved by the IMA-CNMNC.
Mineralogical Magazine, 2013
Štěpite, tetragonal U(AsO3 OH)2(H2O)4 (IMA 2012-006), is the first natural arsenate of tetravalen... more Štěpite, tetragonal U(AsO3 OH)2(H2O)4 (IMA 2012-006), is the first natural arsenate of tetravalent uranium. It occurs in the Geschieber vein, Jáchymov ore district, Western Bohemia, Czech Republic, as emerald-green crystalline crusts on altered arsenic. Associated minerals include arsenolite, běhounekite, claudetite, gypsum, kaatialaite, the new mineral vysokýite (IMA 2012-067) and a partially characterized phase with the formula (H3O)+ 2(UO2)2(AsO4)2˙6H2O. Štěpite typically forms tabular crystals with prominent {001} and {010} faces, up to 0.6 mm in size. The crystals have a vitreous lustre and a grey to greenish grey streak. They are brittle with an uneven fracture and a very good cleavage on (001). Their Mohs hardness is about 2. Štěpite is not fluorescent in either short-wave or long-wave ultraviolet light. It is biaxial (–) with refractive indices (at 590 nm) of α = 1.636(2), β = 1.667(3), γ = 1.672(2) and 2Vobs < ~5°, anomalous greyish to pale yellow interference colours, a...
Mineralogical Magazine, 2013
Švenekite (IMA 99-007), Ca[AsO2(OH)2]2, is a rare supergene arsenate mineral occurring in the Ges... more Švenekite (IMA 99-007), Ca[AsO2(OH)2]2, is a rare supergene arsenate mineral occurring in the Geschieber vein, Jáchymov ore district, Western Bohemia, Czech Republic. It grows directly on the granite rocks and occurs isolated from other arsenate minerals otherwise common in Jáchymov. Švenekite usually forms clear transparent coatings composed of indistinct radiating to rosette-shaped aggregates up to 3 mm across. They are composed of thin lens- or bladed-shaped crystals, usually 100 – 150 μm long. Švenekite is transparent to translucent and has a white streak and a vitreous lustre; it does not fluoresce under ultraviolet light. Cleavage is very good on {010}. The Mohs hardness is ∼2. Švenekite is biaxial, non-pleochroic. The refractive indices are α' = 1.602(2), γ' = 1.658(2). The empirical formula of švenekite (based on As + P + S = 2 a.p.f.u., an average of 10 spot analyses) is (Ca1.00Mg0.01)Σ1.01[AsO2(OH)2]1.96[PO2(OH)2]0.03(SO4)0.01. The simplified formula is Ca[AsO2(OH)...
European Journal of Mineralogy, 2007
ABSTRACT Vihorlatite, ideally Bi24Se17Te4, is a new mineral species found in the region of volcan... more ABSTRACT Vihorlatite, ideally Bi24Se17Te4, is a new mineral species found in the region of volcanic Vihorlat Mountains in eastern Slovakia. It occurs in quartz-opal veinlets or secondary quartzites as anhedral to subhedral grains flattened parallel to (0001) up to 8 mm in diameter or aggregates thereof. The mineral is steel grey in colour and shows a metallic lustre. It displays a perfect cleavage along (0001) and shows deformation lamellae in mechanically bent crystals. In reflected light, it is white with a yellow tint, bireflectance is not perceptible in air, and anisotropy is moderate varying from light yellow-grey to dark grey. Maximum and minimum values of reflectance measured in air for 470, 546, 589 and 650 nm are (R-max/R-min in %): 52.9/49.9, 54.5/50.6, 54.6/51, 54.7/51.2. Vickers micro-hardness (VHN50 in kg/mm(2)) varies in the range 49.2 - 91.7 with mean value of 65.9. Average chemical composition (in wt. %) Bi 71.5, Se 21.4, Te 8.1, S 0.8, Au 0.01, Ag 0.01, Sb 0.04, total 101.86, results in an empirical formula Bi21.9Se17.4Te4.1S1.6. The mineral is trigonal, with space group P (3) over bar m1. The unit-cell dimensions refined from powder data are a = 4.2797(9) angstrom and c'= 87.01(2) angstrom with c/ = 20.332(6) and V= 1380.2(6) angstrom(3). For Z = 1, the calculated density is D-x = 7.850(3) g/cm(3), measured density D-m = 8.0(2) g/cm(3). The five strongest diffraction lines are [d (angstrom), I/I-0, (hkl)]: 4.55, 55.4, (0.0.19); 3.116, 100, (1.0.15); 2.282, 75.5, (0.1.30); 1.934, 42.8, (1.1.19) (0.0.45); 1.767, 31.5, (0.2.15). The crystal structure of vihorlatite is derived from that of Bi8Se7 archetype. Vihorlatite belongs to the tetradymite group.
European Journal of Mineralogy, 2004
ABSTRACT
Journal of Geosciences, 1997
Introduction Torbern Olof Bergman was born in Katrineberg, Sweden, the son of Barthold Bergman, s... more Introduction Torbern Olof Bergman was born in Katrineberg, Sweden, the son of Barthold Bergman, sheriff on the royal estate at Katrineberg. Bergman studied mathematics, philosophy, physics and astronomy at the University of Uppsala, graduating in 1756. He later joined the faculty of the University, teaching physics and mathematics, and succeeded to Wallerius chair as Professor of chemistry in 1767. He developed a growing interest in chemistry, mineralogy and crystallography when demonstrated how the stacking of rhombohedral units could produce a scalenohedron. (Haüy later proposed the same thing but denied having known on Bergman's theories.) [217]. Jáchymov is type locality for 17 secondary minerals. Ten of these minerals were named after persons, including some prominent mineralogists of the 19th century. Interesting biographical data on these personalities were assembled during work on the projects of study of the secondary minerals in the Jáchymov ore district (Grant Agency ...
Journal of Geosciences, 2003
Journal of Geosciences, 1997
Journal of Geosciences, 2003
New naturally occuring mineral phases from Krasno-Horni Slavkov area, western Bohemia, Czech Repu... more New naturally occuring mineral phases from Krasno-Horni Slavkov area, western Bohemia, Czech Republic
American Mineralogist, 1999
Parascorodite, a new mineral from Kaňk near Kutná Hora, Central Bohemia, Czech Republic, forms ea... more Parascorodite, a new mineral from Kaňk near Kutná Hora, Central Bohemia, Czech Republic, forms earthy white to white-yellow aggregates associated with scorodite, pitticite, bukovskýite, kaňkite, zýkaite, gypsum, and jarosite, wet chemical analysis gave (in wt%): As 2 O 5 44.45, P 2 O 5 0.84, SO 3 1.53, Fe 2 O 3 34.55, Al 2 O 3 0.17, H 2 O 17.81, totaling 99.95. The simplified chemical formula is FeAsO 4 •2H 2 O. Selected area electron diffraction suggests hexagonal or trigonal symmetry. The extinction symbol is P-c-. Powder X-ray diffraction yielded unit-cell parameters a = 8.9327(5) Å, c = 9.9391(8) Å, V = 686.83 (8) Å 3 , Z = 6. Densities (measured and calculated, respectively) are D m = 3.213(3) g/cm 3 and D x = 3.212 g/cm 3. SEM and TEM images showed that basal sections of parascorodite are hexagonal in shape; thicker prismatic crystals were also observed. Crystal size varies between 0.1 to 0.5 µm. The strongest lines in the X-ray powder diffraction pattern are [d[I](hkl)]: 4.184(44)(012), 4.076(100)(111), 3.053(67)(202), 2.806(68)(211), 2.661(59)(113), 2.520(54)(212), 2.2891(44)(032). Refractive indexes could not have been measured due to extremely small crystallite size, n-(calc) = 1.797. The TG curve shows two weight losses: at 20-150 °C (2.1 wt%, absorbed water) and at 150-620 °C (15.5 wt%, molecular water), respectively. They correspond to the endothermic peaks on the DTA curve at 120 and 260 °C. Strong exothermic reaction observed at 585 °C reflects formation of the phase FeAsO 4. Infrared absorption spectra of parascorodite are close to those of scorodite.
Journal of Geosciences, 2003
This contribution provides a brief review of geology of the Kruné hory Mts. (Erzgebirge) and spec... more This contribution provides a brief review of geology of the Kruné hory Mts. (Erzgebirge) and specifically of the Jáchymov (Joachimsthal) deposit. Main types of rocks in the Jáchymov ore district and the role of tectonic processes are described. The position of the ore district is defined much like its tectonic borders. Geological factors controlling the mineralization (especially the so-called five-element mineralization) are summarized. Hydrothermal veins are divided into Morning and Midnight veins according to the classical historical speak of miners, and all vein clusters are listed. Vein hydrothermal five-element mineralization is chronologically divided into separate mineralization stages and their age is estimated.
Journal of GEOsciences, 2012
This paper presents results of study of supergene minerals occuring at the Huber stock and Schnöd... more This paper presents results of study of supergene minerals occuring at the Huber stock and Schnöd stock in the Krásno Sn-W ore district near Horní Slavkov (Slavkovský les area, Czech Republic). The mineralogical research is based on X-ray powder diffraction, electron microprobe analyses, optical and electron microscopy. The paper includes encyclopaedia-type presentation of the identified mineral species. The role of late hydrothermal, supergene, sub-recent and recent processes in the formation of minerals and their associations is discussed.
American Mineralogist, 2002
American Mineralogist, 2003
Mineralogical Magazine, 2014
Hloušekite, (Ni,Co)Cu4(AsO4)2(AsO3OH)2(H2O)9, is a new supergene arsenate mineral from the Geiste... more Hloušekite, (Ni,Co)Cu4(AsO4)2(AsO3OH)2(H2O)9, is a new supergene arsenate mineral from the Geister vein (Rovnost mine), Jáchymov (St Joachimsthal), Western Bohemia, Czech Republic. It was found along with veselovský ite, pradetite, lavendulan, arsenolite, babánekite and gypsum on the surface of strongly altered ore fragments containing dominant tennantite and chalcopyrite. Hloušekite forms thin, lath-like crystals, locally elongated reaching up to 3 mm across. It is transparent, has a pale green colour with vitreous lustre, has a greyish-white streak and it is very brittle with an uneven fracture. It does not fluoresce under shortwave or longwave ultraviolet radiation. Cleavage on {010} is perfect; the Mohs hardness is 2–3. The calculated density is 3.295 g cm–3. Hloušekite is optically biaxial with α’ = 1.653(2) and γ’ = 1.73. The estimated optical orientation is γ’ vs. elongation (c) = 14(1)°. In larger grains it is weakly to moderately pleochroic (α = colourless, γ = pale green t...
Journal of GEOsciences, 2012
This paper presents the existing and newly obtained information on supergene minerals of the Horn... more This paper presents the existing and newly obtained information on supergene minerals of the Horní Slavkov uranium ore district. Mineralogical studies confirmed occurrences of the following minerals:
Journal of GEOsciences, 2012
The present detailed research is focused on minerals of phosphate accumulations collected in the ... more The present detailed research is focused on minerals of phosphate accumulations collected in the Huber open pit and at the 5 th level of the Huber shaft, Krásno ore district, Slavkovský les area, Czech Republic. The following minerals have been identified at the studied localities:
Journal of GEOsciences, 2012
Detailed mineralogical study focused on two deposits located on slopes of the Vysoký Kámen hill n... more Detailed mineralogical study focused on two deposits located on slopes of the Vysoký Kámen hill near Krásno in the proximity of the town of Horní Slavkov in Czech Republic. The open pit exploiting industrial feldspar material (mainly feldspathites and aplitic granites) offerred new finds of minerals in the Slavkovský les. The following minerals were identified: autunite, bertrandite, beryl, goethite, hematite, koechlinite, kolbeckite, meta-autunite, powellite and scheelite. In the nearby abandoned greisen deposit a phosphate mineral association was observed consisting of cacoxenite, leucophosphite, vivianite, wavellite and minerals of the chalcosiderite-turquoise and strengite-variscite series. In addition to them dickite and goethite were identified. The genesis of these mineral associations is discussed.
Neues Jahrbuch für Mineralogie - Abhandlungen, 2010
ABSTRACT Veselovskýite, (Zn,Cu,Co)Cu4(AsO4)2(AsO3OH)2 · 9H2O, is a new supergene mineral from the... more ABSTRACT Veselovskýite, (Zn,Cu,Co)Cu4(AsO4)2(AsO3OH)2 · 9H2O, is a new supergene mineral from the Geister vein, Mine Rovnost at the Jáchymov ore district (St. Joachimsthal), Czech Republic, commonly associated with strashimirite and blue amorphous Cu arsenate. It forms aggregates, up to 8 × 5 × 1 mm in size, consisting of lath-like to thin-tabular crystals, up to 1 mm long, commonly forming complicated intergrowths, no twinning was observed. Veselovskýite is translucent (aggregates) to transparent (crystals), colourless to greyish white (with a slight greenish tint). It has a greyish white streak with a greenish tint, a vitreous luster, does not fluoresce under both short- and long-wave ultraviolet light. Cleavage on {001} is perfect, Mohs hardness is ∼2-3, and veselovskýite is very brittle with an irregular fracture and calculated density 3.28 g/cm3. Veselovskýite is biaxial positive, the indices of refraction are nx´ 1.645(3), ny´ 1.68(1), nz´ ∼1.72, 2V(calc) approximative 88°, it is strongly pleochroic (nx = greenish, ny = pale green, nz = green), and the optical orientation is as follows: nx´ versus elongation (c) = 15(1)°. Veselovskýite is triclinic, space group P-1, a 6.4022(4), b 8.0118(4), c 10.3665(4) Å, α 85.491(3)°, β 79.377(4)°, γ 84.704(5)°, V 519.34(4) Å3, Z = 1, a:b:c = 0.7991:1:1.2939. The eight strongest lines in the X-ray powder diffraction pattern are as follows: d (Å), I, (hkl): 10.185, 100 (001), 7.974, 12 (010), 3.987, 13 (020), 3.637, 15 (0-21), 3.395, 37 (003), 3.238, 15 (022), 2.910, 12 (202), 2.668, 16 (023). The chemical analyses by electron microprobe yielded MgO 0.05, CaO 0.04, MnO 0.22, NiO 0.30, CoO 0.96, CuO 32.98, ZnO 3.39, Al2O3 0.24, P2O5,As2O5 43.16, H2O 17.90, total (100.00) wt.%. The resulting empirical formula on the basis of 25 (O, OH, H2O) anions is (Zn0.43Cu0.24Co0.13Al0.05Ni0.04Mn0.03Mg0.01Ca0.01)Σ0.94 Cu4.00 [(AsO4)1.92(PO4)0.11(AsO3OH)1.92] · 9.20H2O. The ideal end-member formula ZnCu4[(AsO4)2(AsO3OH)2] · 9H2O requires ZnO 7.83, CuO 30.61, As2O5 44.22, H2O 17.34, total 100.00 wt.%. Veselovskýite is isostructural with lindackerite and represents Zn-dominant analogue of lindackerite and pradetite. The name veselovskýite is in honor of František Veselovský (*1948), an outstanding Czech mineralogist, who described several new minerals from the Jáchymov ore district.
Mineralogy and Petrology, 2011
The new mineral agricolaite, a potassium uranyl carbonate with ideal formula K 4 (UO 2)(CO 3) 3 ,... more The new mineral agricolaite, a potassium uranyl carbonate with ideal formula K 4 (UO 2)(CO 3) 3 , occurs in vugs of ankerite gangue in gneisses in the abandoned Giftkiesstollen adit at Jáchymov, Czech Republic. The name is after Georgius Agricola (1494-1555), German scholar and scientist. Agricolaite occurs as isolated equant irregular translucent grains to 0.3 mm with yellow color, pale yellow streak, and vitreous luster. It is brittle with uneven fracture and displays neither cleavage nor parting. Agricolaite is non-fluorescent. Mohs hardness is~4. It is associated with aragonite, brochantite, posnjakite, malachite, rutherfordine, and "pseudo-voglite". Experimental density is higher than 3.3 g.cm −3 , Dcalc is 3.531 g.cm −3. The mineral is monoclinic, space group C2/c, with a 10.2380(2), b 9.1930(2), c 12.2110(3) Å, β 95.108(2)°, V 1144.71(4) Å 3 , Z=4. The strongest lines in the powder Xray diffraction pattern are d(I)(hkl): 6.061(55)(002), 5.087 (57)(200), 3.740(100)(202), 3.393(43)(113), 2.281(52) (402). Average composition based on ten electron microprobe analyses corresponds to (in wt.%) UO 3 48.53, K 2 O 31.49, CO 2 (calc) 22.04 which gives the empirical formula K 3.98 (UO 2) 1.01 (CO 3) 3.00. The crystal structure was solved from single-crystal X-ray diffraction data and refined to R 1 =0.0184 on the basis of the 1,308 unique reflections with F o >4σF o. The structure of agricolaite is identical to that of synthetic K 4 (UO 2)(CO 3) 3 and consists of separate UO 2 (CO 3) 3 groups organized into layers parallel to (100) and two crystallographically non-equivalent sites occupied by K + cations. Both the mineral and its name were approved by the IMA-CNMNC.
Mineralogical Magazine, 2013
Štěpite, tetragonal U(AsO3 OH)2(H2O)4 (IMA 2012-006), is the first natural arsenate of tetravalen... more Štěpite, tetragonal U(AsO3 OH)2(H2O)4 (IMA 2012-006), is the first natural arsenate of tetravalent uranium. It occurs in the Geschieber vein, Jáchymov ore district, Western Bohemia, Czech Republic, as emerald-green crystalline crusts on altered arsenic. Associated minerals include arsenolite, běhounekite, claudetite, gypsum, kaatialaite, the new mineral vysokýite (IMA 2012-067) and a partially characterized phase with the formula (H3O)+ 2(UO2)2(AsO4)2˙6H2O. Štěpite typically forms tabular crystals with prominent {001} and {010} faces, up to 0.6 mm in size. The crystals have a vitreous lustre and a grey to greenish grey streak. They are brittle with an uneven fracture and a very good cleavage on (001). Their Mohs hardness is about 2. Štěpite is not fluorescent in either short-wave or long-wave ultraviolet light. It is biaxial (–) with refractive indices (at 590 nm) of α = 1.636(2), β = 1.667(3), γ = 1.672(2) and 2Vobs < ~5°, anomalous greyish to pale yellow interference colours, a...
Mineralogical Magazine, 2013
Švenekite (IMA 99-007), Ca[AsO2(OH)2]2, is a rare supergene arsenate mineral occurring in the Ges... more Švenekite (IMA 99-007), Ca[AsO2(OH)2]2, is a rare supergene arsenate mineral occurring in the Geschieber vein, Jáchymov ore district, Western Bohemia, Czech Republic. It grows directly on the granite rocks and occurs isolated from other arsenate minerals otherwise common in Jáchymov. Švenekite usually forms clear transparent coatings composed of indistinct radiating to rosette-shaped aggregates up to 3 mm across. They are composed of thin lens- or bladed-shaped crystals, usually 100 – 150 μm long. Švenekite is transparent to translucent and has a white streak and a vitreous lustre; it does not fluoresce under ultraviolet light. Cleavage is very good on {010}. The Mohs hardness is ∼2. Švenekite is biaxial, non-pleochroic. The refractive indices are α' = 1.602(2), γ' = 1.658(2). The empirical formula of švenekite (based on As + P + S = 2 a.p.f.u., an average of 10 spot analyses) is (Ca1.00Mg0.01)Σ1.01[AsO2(OH)2]1.96[PO2(OH)2]0.03(SO4)0.01. The simplified formula is Ca[AsO2(OH)...
European Journal of Mineralogy, 2007
ABSTRACT Vihorlatite, ideally Bi24Se17Te4, is a new mineral species found in the region of volcan... more ABSTRACT Vihorlatite, ideally Bi24Se17Te4, is a new mineral species found in the region of volcanic Vihorlat Mountains in eastern Slovakia. It occurs in quartz-opal veinlets or secondary quartzites as anhedral to subhedral grains flattened parallel to (0001) up to 8 mm in diameter or aggregates thereof. The mineral is steel grey in colour and shows a metallic lustre. It displays a perfect cleavage along (0001) and shows deformation lamellae in mechanically bent crystals. In reflected light, it is white with a yellow tint, bireflectance is not perceptible in air, and anisotropy is moderate varying from light yellow-grey to dark grey. Maximum and minimum values of reflectance measured in air for 470, 546, 589 and 650 nm are (R-max/R-min in %): 52.9/49.9, 54.5/50.6, 54.6/51, 54.7/51.2. Vickers micro-hardness (VHN50 in kg/mm(2)) varies in the range 49.2 - 91.7 with mean value of 65.9. Average chemical composition (in wt. %) Bi 71.5, Se 21.4, Te 8.1, S 0.8, Au 0.01, Ag 0.01, Sb 0.04, total 101.86, results in an empirical formula Bi21.9Se17.4Te4.1S1.6. The mineral is trigonal, with space group P (3) over bar m1. The unit-cell dimensions refined from powder data are a = 4.2797(9) angstrom and c'= 87.01(2) angstrom with c/ = 20.332(6) and V= 1380.2(6) angstrom(3). For Z = 1, the calculated density is D-x = 7.850(3) g/cm(3), measured density D-m = 8.0(2) g/cm(3). The five strongest diffraction lines are [d (angstrom), I/I-0, (hkl)]: 4.55, 55.4, (0.0.19); 3.116, 100, (1.0.15); 2.282, 75.5, (0.1.30); 1.934, 42.8, (1.1.19) (0.0.45); 1.767, 31.5, (0.2.15). The crystal structure of vihorlatite is derived from that of Bi8Se7 archetype. Vihorlatite belongs to the tetradymite group.
European Journal of Mineralogy, 2004
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