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The new mineral markeyite (IMA2016-090), Ca9(UO2)4(CO3)13·28H2O, was found in the Markey mine, San Juan County, Utah, USA, where it occurs as a secondary phase on asphaltum in association with calcite, gypsum and natrozippeite. The mineral is pale yellowish-green with white streak and fluoresces bright bluish white under a 405 nm laser. Crystals are transparent and have vitreous to pearly lustre. It is brittle, with Mohs hardness 1 1/2 to 2, irregular fracture and three cleavages: perfect on {001}; good on {100} and {010}. The measured density is 2.68 g cm⁻³. Crystals are blades, flattened on {001} and elongate on [010], exhibiting the forms {100}, {010}, {001}, {110}, {101}, {011} and {111}. Markeyite is optically biaxial (-) with α = 1.538(2), β = 1.542(2) and γ = 1.545(2) (white light); the measured 2V is 81(2)°; the dispersion is r < v (weak); the optical orientation is X = c, Y = b, Z = a; and pleochroism is X = light greenish yellow, Y and Z = light yellow (X > Y ≈ Z). Electron microprobe analyses (energy-dispersive spectroscopy mode) yielded CaO 18.60, UO3 42.90, CO2 21.30 (calc.) and H2O 18.78 (calc.), total 101.58 wt.% and the empirical formula Ca8.91(U1.01O2)4(CO3)13·28H2O. The six strongest powder X-ray diffraction lines are [dobs A(I)(hkl)]: 10.12(69)(001), 6.41(91)(220,121), 5.43(100)(221), 5.07(33)(301,002,131), 4.104(37)(401,141) and 3.984(34)(222). Markeyite is orthorhombic, Pmmn, a = 17.9688(13), b = 18.4705(6), c = 10.1136(4) A, V = 3356.6(3) A³ and Z = 2. The structure of markeyite (R1 = 0.0435 for 3427 Fo > 4σF) contains uranyl tricarbonate clusters (UTC) that are linked by Ca-O polyhedra forming thick corrugated heteropolyhedral layers. Included within the layers is an additional disordered CO3 group linking the Ca-O polyhedra. The layers are linked to one another and to interlayer H2O groups only via hydrogen bonds. The structure bears some similarities to that of liebigite.
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This is a 'preproof' accepted article for Mineralogical Magazine. This version may be subject to change during the
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DOI: 10.1180/minmag.2017.081.085.
Markeyite, a new calcium uranyl carbonate mineral from the Markey mine, San Juan
County, Utah, USA
Anthony R. Kampf1*, Jakub Plášil2, Anatoly V. Kasatkin3, Joe Marty4 and Jiří Čejka5
1 Mineral Sciences Department, Natural History Museum of Los Angeles County, 900
Exposition Boulevard, Los Angeles, CA 90007, USA
2 Institute of Physics ASCR, v.v.i., Na Slovance 1999/2, 18221 Prague 8, Czech Republic
3 Fersman Mineralogical Museum of the Russian Academy of Sciences, Leninsky Prospekt,
18-2, 119071, Moscow, Russia
4 5199 East Silver Oak Road, Salt Lake City, UT 84108, USA
5 Department of Mineralogy and Petrology, National Museum, Cirkusová 1740, 193 00,
Prague 9, Czech Republic
*E-mail: akampf@nhm.org
[Received 3 July 2017; Accepted 19 October 2017; Associate Editor: Ian Graham]
Abstract
The new mineral markeyite (IMA2016-090), Ca9(UO2)4(CO3)13·28H2O, was found in
the Markey mine, San Juan County, Utah, USA, where it occurs as a secondary phase on
asphaltum in association with calcite, gypsum and natrozippeite. The mineral is pale
yellowish-green with white streak and fluoresces bright bluish white under a 405 nm laser.
Crystals are transparent and have vitreous to pearly luster. It is brittle, with Mohs hardness 1½
to 2, irregular fracture and three cleavages: perfect on {001}; good on {100} and {010}. The
measured density is 2.68 g cm-3. Crystals are blades, flattened on {001} and elongate on
[010], exhibiting the forms {100}, {010}, {001}, {110}, {101}, {011} and {111}. Markeyite
is optically biaxial () with α = 1.538(2), β = 1.542(2) and γ = 1.545(2) (white light); the
measured 2V is 81(2; the dispersion is r < v (weak); the optical orientation is X = c, Y = b, Z
= a; and pleochroism is X light greenish yellow, Y and Z light yellow (X > Y Z). Electron
microprobe analyses (EDS mode) yielded CaO 18.60, UO3 42.90, CO2 21.30 (calc.) and H2O
18.78 (calc.), total 101.58 wt.% and the empirical formula Ca8.91(U1.01O2)4(CO3)13·28H2O.
The six strongest X-ray powder diffraction lines are [dobs Å(I)(hkl)]: 10.12(69)(001),
6.41(91)(220,121), 5.43(100)(221), 5.07(33)(301,002,131), 4.104(37)(401,141) and
3.984(34)(222). Markeyite is orthorhombic, Pmmn, a = 17.9688(13), b = 18.4705(6), c =
10.1136(4) Å, V = 3356.6(3) Å3 and Z = 2. The structure of markeyite (R1 = 0.0435 for 3427
Fo > 4F) contains uranyl tricarbonate clusters (UTC) that are linked by CaO polyhedra
forming thick corrugated heteropolyhedral layers. Included within the layers is an additional
disordered CO3 group linking the CaO polyhedra. The layers are linked to one another and to
interlayer H2O groups only via hydrogen bonds. The structure bears some similarities to that
of liebigite.
Keywords: markeyite; new mineral; uranyl tricarbonate; crystal structure; liebigite; Markey
mine, Utah, USA
Introduction
In recent years, mines in the Red Canyon portion of the White Canyon district in
south-eastern Utah have yielded many new minerals. Our investigation of the secondary
mineralisation at the Blue Lizard mine has already resulted in the description of sixteen new
minerals, most of which are Na uranyl sulfates. As we have expanded our efforts to other
nearby uranium mines in Red Canyon, additional new species are being revealed. The new
Na-Mg uranyl carbonate leószilárdite (Olds et al., 2016) was recently described from the
Markey mine and, herein, we describe another new uranyl carbonate, markeyite, from this
mine.
Markeyite (/ma:r 'ki: ait/) is named for the locality, the Markey mine. The new
mineral and name were approved by the Commission on New Minerals, Nomenclature and
Classification of the International Mineralogical Association (IMA2016-090). After the initial
approval of the mineral and its publication in the CNMNC Newsletter No. 35 (Kampf et al.,
2017), a change in the formula from Ca9(UO2)4(CO3)12(OH)2·28H2O to
Ca9(UO2)4(CO3)13·28H2O was approved by the officers of the CNMNC (Hålenius et al.
2017). The description is based on one holotype and five cotype specimens. The holotype and
four cotypes are deposited in the collections of the Natural History Museum of Los Angeles
County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA, catalogue numbers 67091
(holotype), 67092, 67093, 67094 and 69095, respectively. One cotype specimen is housed in
the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences,
Moscow, Russia, registration number 4932/1.
Occurrence
Markeyite was found underground in the Markey mine, Red Canyon, White Canyon
District, San Juan County, Utah, USA (37°32'57"N 110°18'08"W). The Markey mine is
located about 1 km southwest of the Blue Lizard mine, on the east-facing side of Red Canyon,
about 72 km west of the town of Blanding, Utah, and about 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).
Jim Rigg of Grand Junction, Colorado began staking claims in Red Canyon in March
of 1949. The Markey group of claims, staked by Rigg and others, was purchased by the
Anaconda Copper Mining Company on June 1, 1951. After limited exploration and
production, the mine closed in 1955. The mine was subsequently acquired from Anaconda by
Calvin Black of Blanding, Utah under whose ownership the mine operated from 1960 to 1982
and was a leading producer in the district for nearly that entire period.
The uranium deposits in Red Canyon occur within the Shinarump member of the
Upper Triassic Chinle Formation, in channels incised into the reddish-brown siltstones of the
underlying Lower Triassic Moenkopi Formation. The Shinarump member consists of
medium- to coarse-grained sandstone, conglomeratic sandstone beds and thick siltstone
lenses. Ore minerals were deposited as replacements of wood and other organic material and
as disseminations in the enclosing sandstone. Since the mine closed in 1982, oxidation of
primary ores in the humid underground environment has produced a variety of secondary
minerals, mainly carbonates and sulfates, as efflorescent crusts on the surfaces of mine walls.
Markeyite is a rare mineral in the secondary mineral assemblage at the Markey mine.
It occurs on asphaltum in association with calcite, gypsum and natrozippeite. Other secondary
minerals in the general assemblage include ammoniozippeite, andersonite, anglesite,
aragonite, arsenuranospathite, atacamaite, bayleyite, bluelizardite, bobcookite, brochantite,
čejkaite, chalcanthite, chalconatronite, chinleite-(Y), covellite, cuprosklodowskite,
cyanotrichite, deliensite, devilline, erythrite, eugsterite, fermiite, jarosite, johannite,
klaprothite, leószilárdite, leydetite, magnesioleydetite, mahnertite, malachite, marécottite,
melanterite, metakahlerite, metasideronatrite, natrojarosite, plašilite, posnjakite,
pseudojohannite, redcanyonite, romerite, sabugalite, shröckingerite, sideronatrite, sulfur,
thenardite, thérèsemagnanite, uramarsite, uranospathite, wetherillite, zippeite and and other
potentially new minerals currently under investigation.
Physical and optical properties
Markeyite crystals are blades and tablets (Fig. 1) up to about 1 mm in maximum
dimension, flattened on {001} and elongate on [010]. Measurements on a Huber Reflection
Goniometer 302 confirmed the crystal the forms {100}, {010}, {001}, {110}, {101}, {011}
and {111} (Fig. 2). No twinning was observed.
Crystals are pale yellowish green and transparent with vitreous lustre. The streak is
white. The mineral fluoresces bright bluish white under a 405 nm laser. The Mohs hardness is
between 1½ and 2, based upon scratch tests. Crystals are brittle with irregular fracture and
three cleavages: perfect on {001}, good on {100} and {010}. At room temperature, the
mineral dissolves very slowly in H2O (minutes) and dissolves immediately with effervescence
in dilute HCl. The density measured by floatation in a mixture of methylene iodide and
toluene is 2.68(2) g/cm3. The calculated density based on the empirical formula and unit-cell
parameters obtained from single-crystal X-ray diffraction data is 2.699 g/cm3.
Optically, markeyite is biaxial (), with α = 1.538(1), β = 1.542(1), γ = 1.545(1)
(measured in white light). The 2V measured directly on a spindle-stage is 81(2; the
calculated 2V is 81.6°. Dispersion is r < v, weak. The mineral is weakly pleochroic: X = light
greenish yellow, Y ≈ Z = light yellow; X > Y Z. The optical orientation is X = c, Y = b, Z = a.
Raman Spectroscopy
Raman spectroscopy was conducted on a Horiba XploRA PLUS using a 785 nm diode
laser. A background correction was applied using the Horiba software. The Raman spectrum
of markeyite is shown in Figure 3.
The broad multiple bands in the 3700-3300 and 2800-2300 cm-1 ranges are attributed
to O-H stretching vibrations of structurally nonequivalent/symmetrically distinct hydrogen-
bonded OH and H2O groups. The 3700-3300 cm-1 range corresponds to weak hydrogen bonds
and the 2800-2300 cm-1 range to strong hydrogen bonds (Libowitzky, 1999). A weak, broad
band centred at about 1600 cm1 is attributed to the 2() bending vibrations of H2O.
The aforementioned H2O band partly overlaps with a very weak broad band associated
with the split doubly degenerate 3 (CO3)2- antisymmetric stretching vibrations of the (CO3)2-
units, with a more distinct weak band at 1412 cm-1. Medium to strong bands at 1095, 1086,
1078 and 1067 cm-1 are connected with the 1 (CO3)2- symmetric stretching vibrations. These
bands are consistent with the presence of four structurally nonequivalent carbonate units
(Koglin et al., 1979; Anderson et al., 1980; Čejka, 1999 and 2005, and references therein), but
do not preclude the presence of a fifth carbonate unit.
A weak band at 882 cm-1 may be due to the 2 () (CO3)2- bending vibrations or to the
3 (UO2)2+ antisymmetric stretching vibration corresponding with the U-O bond length in
uranyl at approximately 1.80 Å; an overlap/coincidence of these two bands is possible. A very
strong band at 825 cm-1 is assigned to the 1 (UO2)2+ symmetric stretching vibrations and
provides an inferred U-O bond length of approximately 1.79 Å (Bartlett and Cooney, 1989).
Also a coincidence of the 2 () (CO3)2- bending vibration and 1 (UO2)2+ symmetric
stretching vibration is likely.
Weak to strong bands at 772, 751, 733 and 694 cm-1 are assigned to the doubly
degenerate 4 () (CO3)2- bending vibrations. A medium broad band at 238 cm-1 is assigned to
the split doubly degenerate 2 () (UO2)2+ bending vibrations and weak to medium bands at
170, 155 and 128 cm-1 to the lattice modes (Koglin et al., 1979; Anderson et al., 1980; Čejka,
1999 and 2005).
Chemical composition
Chemical analyses (9) were performed using a CamScan 4D electron microprobe in
EDS mode (20 kV, 5 nA, 3 μm beam diameter). Attempts to use WDS mode with higher
beam current were made, but resulted in partial dehydration and totals significantly higher
than 100 wt%. H2O and CO2 were not determined directly because of extreme paucity of
material. The H2O and CO2 contents were calculated by stoichiometry on the basis of 75 O
apfu and confirmed by the crystal structure refinement and Raman spectroscopy. No other
elements with atomic numbers higher than 8 were observed. Analytical data are given in
Table 1.
The empirical formula is Ca8.91(U1.01O2)4(CO3)13·28H2O. The ideal formula is
Ca9(UO2)4(CO3)13·28H2O which requires CaO 18.52, UO3 41.98, CO2 20.99 and H2O 18.51,
total 100 wt%. The Gladstone-Dale compatibility index 1 (KP/KC) for the empirical formula
is -0.027, in the excellent range (Mandarino, 2007), using k(UO3) = 0.118, as provided by
Mandarino (1976).
X-ray crystallography and structure refinement
Powder X-ray studies were done using a Rigaku R-Axis Rapid II curved imaging plate
microdiffractometer, with monochromatised MoKα radiation ( = 0.71075 Å). A Gandolfi-
like motion on the and axes was used to randomize the sample and observed d-values and
intensities were derived by profile fitting using JADE 2010 software (Materials Data, Inc.).
The powder data presented in Table 2 show good agreement with the pattern calculated from
the structure determination. Unit-cell parameters refined from the powder data using JADE
2010 with whole pattern fitting are: a = 17.9688(13), b = 18.4705(6), c = 10.1136(4) Å and V
= 3356.6(3) Å3.
The single-crystal structure data were collected at room temperature using the same
diffractometer and radiation noted above. The data were processed using the Rigaku
CrystalClear software package and an empirical (multi-scan) absorption correction was
applied using the ABSCOR program (Higashi, 2001) in the CrystalClear software suite. The
structure was solved by direct methods using SIR2011 (Burla et al., 2012). SHELXL-2013
(Sheldrick, 2015) was used for the refinement of the structure.
Determining the locations of most atoms was straightforward. The initial structure
determination showed that the O15 site, nearly fully occupied by O, is only 2.28 Å from an
equivalent O15 site. We first thought that the short O15O15 distance could be indicative of a
very strong hydrogen bond; however, the distance is typical for an OO edge of a CO3 group.
Closer examination of difference Fourier maps revealed that two partially-occupied CO3
groups (centred by C5) share this O15O15 edge and are completed by a partially occupied O
site, O16. In subsequent refinements, the occupancies of the C5 and O16 sites were refined as
equivalent. Another partially occupied O site (OH) was located 1.43 Å from the O16 site and
1.31 Å from OW7 on the opposite side. The OH site cannot be occupied when either the O16
or OW7 site is occupied. In subsequent refinements, the occupancies of the OW7 and OH
sites were refined with a combined occupancy of 1.0. The aforementioned sites are shown in
Figure 4. There are three other partially occupied O sites, OW10, OW11 and OW12. The
OW11 and OW12 sites are separated by only 1.41 Å; consequently, their occupancies were
refined with a combined occupancy of 1.0. In the final refinement, soft distance restraints
were placed on the distances between the atoms in the C5O3 group, which slightly improved
the refinement and bond valence sums (BVS). All sites, except the low-occupancy OW12 site,
were refined with anisotropic displacement parameters.
Data collection and refinement details are given in Table 3, atom coordinates and
displacement parameters in Table 4, selected bond distances in Table 5, and a bond-valence
analysis in Table 6.
Description and discussion of the structure
Two U sites (U1 and U2) in the structure of markeyite are each surrounded by eight O
atoms forming a squat UO8 hexagonal bipyramid. These bipyramids are each chelated by
three CO3 groups, forming uranyl tricarbonate clusters (UTC) of formula [(UO2)(CO3)3]4-
(Burns 2005; Fig. 5). There are three different CaO polyhedra in the structure. Ca1 bonds to
7 fully occupied O sites, Ca2 bonds to five fully occupied and five partially occupied O sites
(Fig. 4) for a total effective coordination of 8.27 and Ca3 bonds to five fully occupied and 4
partially occupied O sites for a total effective coordination of 7. The three CaO polyhedra
share edges and corners with the UTCs in very different ways. The Ca1 polyhedra share edges
with U1 and U2 bipyramids and corners with C1 and C2 triangles in different UTCs. Pairs of
Ca2 polyhedra share an edge to form a dimer, which is linked to a second dimer through the
partially occupied C5 triangles and OH and OW7 sites. The group of four Ca2 polyhedra (and
C5 triangle) is linked to two U1 UTCs by edge sharing between Ca2 polyhedra and C1
triangles. The Ca3 polyhedra share corners with two C3 and two C4 triangles, each being in a
different UTC. The linkages between UTCs and Ca polyhedra form thick corrugated
heteropolyhedral layers parallel to {010} (Fig. 5) and these layers link to one another and to
interlayer H2O groups (OW3, OW8 and OW10) only via hydrogen bonds (Fig. 6).
The formula based upon the refined structure is
Ca9(UO2)4(CO3)12.71(OH)0.50·28.25H2O. The ideal formula assumes full occupancy of the O15
site and half occupancy of the C5 and O16 sites, providing one CO3 group pfu. The OH site,
with an occupancy of 0.25, is combined with the nearby OW7 site, with a refined occupancy
of 0.75. The resultant ideal formula is Ca9(UO2)4(CO3)13·28H2O.
The structure of liebigite, Ca2(UO2)(CO3)3·11H2O (Mereiter, 1982), contains the same
structural components as that of markeyite. The same types of polyhedral linkages occur in
both structures. As in the structure of markeyite, the CaO polyhedra link the UTCs in the
structure of liebigite forming thick corrugated heteropolyhedral layers and these layers link to
one another and to interlayer H2O groups only via hydrogen bonds (Fig. 5). However,
topologies of the two structures are quite different. Of particular note, in the liebigite
structure, one of the CaO polyhedra shares an edge with a CO3 group of the UTC, but there
is no such linkage in the markeyite structure.
Acknowledgements
Igor Pekov and an anonymous reviewer are thanked for their constructive comments
on the manuscript. An anonymous CNMNC member is thanked for pointing out the
likelihood that the short O15O15 distance corresponds to the edge of an additional CO3
group. A portion of this study was funded by the John Jago Trelawney Endowment to the
Mineral Sciences Department of the Natural History Museum of Los Angeles County. This
research was also financially supported by GACR post-doctoral Grant no. 13-31276P to J.P.
and by the long-term project DKRVO 2016-02 of the Ministry of Culture of the Czech
Republic (National Museum 00023272) to J.Č.
References
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modifications approved in 2017. CNMNC Newsletter No. 38, August 2017, page 1038;
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Higashi, T. (2001) ABSCOR. Rigaku Corporation, Tokyo.
Kampf, A.R., Plášil, J., Kasatkin, A.V., Marty, J. and Čejka, J. (2016) Klaprothite, péligotite
and ottohahnite, three new sodium uranyl sulfate minerals with bidentate UO7SO4
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Koglin E., Schenk H.J. and Schwochau K. (1979) Vibrational and low temperature optical
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FIGURE CAPTIONS
Figure 1. Markeyite (blades in center) with similar new Ca uranyl carbonate (tapering crystals
along bottom) and calcite (brown and gray balls) on asphaltum; FOV 1.6 mm across.
Figure 2. Crystal drawing of markeyite; clinographic projection in nonstandard orientation,
[010] vertical.
Figure 3. The Raman spectrum of markeyite.
Figure 4. The grouping of Ca2 polyhedra in markeyite, viewed down [001], showing the
linkage by the partially occupied C5 carbonate group, OH and OW7.
Figure 5. The uranyl tricarbonate cluster (UTC) of formula [(UO2)(CO3)3]4-.
Figure 6. The heteropolyhedral layer in markeyite.
Figure 7. The structures of markeyite and liebigite viewed parallel to the heteropolyhedral
layers. UO8 hexagonal bipyramids are dark blue, CO3 triangles are yellow and CaO
polyhedra are light blue; O atoms of isolated H2O groups are white balls. Unit cells outlines
are shown as dashed black lines.
Table 1. Chemical composition (in wt%) for markeyite.
Constituent
Mean
Range
Standard
CaO
18.60
17.87-19.34
wollastonite
UO3
42.90
41.10-44.60
syn. UO2
CO2*
21.30
H2O*
18.78
Total
101.58
* Based on the structure.
Table 2. Powder X-ray diffraction data (d in Å) for markeyite. Only calculated lines with I ≥ 2
are listed.
Iobs
dobs
dcalc
Icalc
hkl
Iobs
dobs
dcalc
Icalc
hkl
Iobs
dobs
dcalc
Icalc
hkl
69
10.12
10.1136
100
0 0 1
2.9450
3
0 6 1
21
2.0518
2.0656
2
8 3 1
9.2353
2
0 2 0
22
2.921
2.9378
6
3 0 3
2.0550
3
5 1 4
13
8.77
8.9844
3
2 0 0
2.9122
5
2 6 0
2.0468
2
5 5 3
6
8.11
7.9543
3
1 1 1
2.9062
4
1 6 1
2.0451
3
2 8 2
6.7168
3
2 0 1
2.9014
2
3 1 3
2.0423
3
7 0 3
91
6.41
6.4398
42
2 2 0
7
2.876
2.8932
2
5 1 2
19
2.0198
2.0299
3
7 1 3
6.3760
16
1 2 1
2.8715
3
6 0 1
2.0244
3
2 7 3
23
5.75
5.8244
6
1 3 0
2.8488
3
6 2 0
2.0179
2
5 2 4
5.6975
13
3 1 0
2.8310
3
2 5 2
1.9988
3
1 9 1
100
5.43
5.4321
68
2 2 1
23
2.806
2.8087
2
2 3 3
1.9941
2
7 2 3
33
5.07
5.1536
9
3 0 1
2.7996
11
3 2 3
22
1.9794
1.9807
3
8 4 1
5.0568
6
0 0 2
2.7923
2
5 2 2
1.9759
3
0 2 5
5.0473
18
1 3 1
25
2.732
2.7461
2
4 5 1
1.9733
3
2 0 5
9
4.920
4.9640
3
3 1 1
2.7421
11
6 2 1
18
1.9455
1.9605
4
5 7 2
4.8677
7
1 0 2
2.7160
7
4 4 2
1.9457
2
7 5 2
25
4.618
4.6176
10
0 4 0
2.6921
2
1 4 3
1.9415
3
3 9 0
4.5386
3
2 3 1
7
2.651
2.6452
3
5 3 2
1.9319
2
6 0 4
4.5003
2
3 2 1
2.6295
3
0 6 2
12
1.9074
1.9067
2
3 9 1
13
4.488
4.4922
7
4 0 0
19
2.521
2.5394
3
4 6 0
1.9049
2
0 8 3
4.4354
2
0 2 2
2.5278
5
1 7 1
14
1.8665
1.8692
2
8 0 3
4.4067
2
2 0 2
2.5236
5
2 6 2
1.8678
2
7 4 3
9
4.301
4.3062
6
1 2 2
2.5037
2
1 0 4
1.8665
3
9 3 1
22
4.199
4.2005
19
0 4 1
11
2.469
2.4820
4
6 2 2
1.8635
2
2 8 3
37
4.104
4.1054
25
4 0 1
2.4658
2
7 1 1
8
1.8431
1.8471
3
0 10 0
4.0902
6
1 4 1
2.4559
2
2 7 1
1.8433
2
6 3 4
34
3.984
3.9772
27
2 2 2
3
2.436
2.4372
4
5 1 3
13
1.8101
1.8146
2
2 4 5
15
3.827
3.8639
8
3 0 2
2.4165
3
1 2 4
1.8087
2
4 2 5
3.8185
3
1 3 2
3
2.375
2.3760
4
5 2 3
18
1.7869
1.7943
3
8 5 2
3.8052
2
2 4 1
8
2.318
2.3285
4
4 4 3
1.7928
2
7 1 4
3.7820
5
3 1 2
2.3197
3
1 7 2
1.7890
3
2 7 4
11
3.591
3.6184
6
1 5 0
2.2889
3
7 0 2
1.7873
2
7 5 3
3.5834
3
2 3 2
15
2.265
2.2716
3
7 1 2
11
1.7541
1.7530
3
0 9 3
3.5645
4
3 2 2
2.2693
2
4 6 2
1.7512
2
4 9 2
11
3.383
3.4099
5
0 4 2
2.2638
5
2 7 2
8
1.6889
1.6889
2
9 2 3
3.4069
2
1 5 1
2.2586
3
3 2 4
1.6844
2
4 10 1
3.3584
8
4 0 2
2.2217
2
7 2 2
7
1.6658
1.6750
2
2 8 4
12
3.344
3.3501
3
1 4 2
2.2177
2
0 4 4
1.6582
2
0 2 6
3.3308
3
5 1 1
12
2.190
2.2038
3
2 6 3
1.6567
2
2 0 6
3.3164
3
0 1 3
2.1834
2
2 8 1
7
1.6126
1.6202
2
8 7 2
5
3.217
3.2199
6
4 4 0
2.1779
4
4 5 3
1.6030
2
7 9 0
7
3.161
3.1668
5
0 2 3
2.1531
2
2 4 4
16
1.5897
1.5940
2
4 8 4
3.1187
3
1 2 3
9
2.134
2.1432
3
4 2 4
1.5921
2
9 7 0
11
3.086
3.1037
5
5 3 0
2.1269
2
5 7 0
1.5909
2
5 5 5
3.0784
2
0 6 0
19
2.091
2.1080
5
7 5 0
1.5832
3
7 9 1
3.0682
3
4 4 1
2.1003
2
0 8 2
9
1.5691
1.5728
2
9 7 1
21
2.987
3.0024
6
3 5 1
2.0861
2
1 8 2
5
1.5477
1.5594
2
2 4 6
2.9948
4
6 0 0
2.0814
5
5 7 1
1.5556
2
4 2 6
2.9867
4
2 2 3
2.0726
2
1 5 4
8
1.5217
1.5280
2
7 9 2
2.9671
4
5 3 1
1.5186
2
9 7 2
6
1.4999
1.5003
2
2 12 1
7
1.4746
1.4779
3
11 5 1
Table 3. Data collection and structure refinement details for markeyite.*
Diffractometer Rigaku R-Axis Rapid II
X-ray radiation/power MoK ( = 0.71075 Å)/50 kV, 40 mA
Temperature 293(2) K
Structural Formula Ca9(UO2)4(CO3)12.71(OH)0.50·28.25H2O
Space group Pmmn
Unit cell dimensions a = 17.9688(13) Å
b = 18.4705(6) Å
c = 10.1136(4) Å
V 3356.6(3) Å3
Z 2
Density (for above formula) 2.692 g cm-3
Absorption coefficient 10.45 mm1
F(000) 2561
Crystal size 110 × 80 × 10 m
range 3.16 to 27.49°
Index ranges –23 ≤ h ≤ 22, –23 ≤ k ≤ 22, –13 ≤ l ≤ 13
Reflections collected/unique 22867/4045; Rint = 0.062
Reflections with F > 4F 3427
Completeness to = 27.44° 98.8%
Max./min. transmission 0.903/0.393
Refinement method Full-matrix least-squares on F2
Restraints/parameters 3/280
GoF 1.054
Final R indices [F > 4(F)] R1 = 0.0435, wR2 = 0.0987
R indices (all data) R1 = 0.0544, wR2 = 0.1034
Largest diff. peak/hole +3.60/2.28 e·A-3
*Rint = |Fo2Fo2(mean)|/[Fo2]. GoF = S = {[w(Fo2Fc2)2]/(np)}1/2. R1 = ||Fo||Fc||/|Fo|.
wR2 = {[w(Fo2Fc2)2]/[w(Fo2)2]}1/2; w = 1/[2(Fo2)+(aP)2+bP] where a is 0.0420, b is
40.5434 and P is [2Fc2+Max(Fo2,0)]/3.
Table 4. Atom coordinates and displacement parameters (Å2) for markeyite.
x/a y/b z/c Ueq U11 U22 U33 U23 U13 U12
U1 0.47538(2) 0.75 0.98772(4) 0.02223(12) 0.0223(2) 0.0189(2) 0.0255(2) 0 -0.00475(16) 0
U2 0.25 0.46729(2) 0.07707(4) 0.02281(12) 0.01450(18) 0.0305(2) 0.0234(2) -0.00413(16) 0 0
Ca1 0.44024(8) 0.43680(8) 0.87250(15) 0.0195(3) 0.0151(6) 0.0205(7) 0.0228(8) 0.0009(6) -0.0009(5) -0.0001(6)
Ca2 0.37570(10) 0.63955(10) 0.61086(18) 0.0346(4) 0.0363(9) 0.0376(10) 0.0298(9) -0.0053(7) -0.0032(7) 0.0061(8)
Ca3 0.25 0.25 0.6838(4) 0.0347(8) 0.0196(15) 0.0254(17) 0.059(3) 0 0 0
C1 0.4296(4) 0.6138(4) 0.8744(8) 0.0244(16) 0.027(4) 0.024(4) 0.023(4) -0.002(3) 0.001(3) -0.005(3)
C2 0.6094(4) 0.4956(4) 0.8050(8) 0.0240(16) 0.020(3) 0.031(4) 0.021(4) 0.004(3) -0.004(3) -0.003(3)
C3 0.25 0.4050(6) 0.8168(11) 0.025(2) 0.023(5) 0.032(6) 0.022(6) -0.006(5) 0 0
C4 0.4235(6) 0.25 0.7923(12) 0.026(2) 0.024(5) 0.022(5) 0.034(6) 0 -0.010(5) 0
C5 0.25 0.7230(15) 0.576(3) 0.030(9) 0.027(18) 0.022(14) 0.04(2) -0.012(13) 0 0
O1 0.4097(3) 0.5575(3) 0.8153(6) 0.0270(12) 0.032(3) 0.018(3) 0.031(3) -0.002(2) -0.007(2) 0.001(2)
O2 0.4704(3) 0.6158(3) 0.9798(5) 0.0286(13) 0.035(3) 0.023(3) 0.028(3) 0.002(2) -0.013(2) 0.004(2)
O3 0.4096(3) 0.6771(3) 0.8283(6) 0.0336(14) 0.044(4) 0.020(3) 0.036(3) -0.001(2) -0.020(3) 0.000(3)
O4 0.5499(3) 0.4702(3) 0.7577(6) 0.0287(13) 0.017(3) 0.038(3) 0.030(3) 0.000(2) -0.001(2) -0.007(2)
O5 0.6721(3) 0.4931(4) 0.7421(6) 0.0371(15) 0.015(2) 0.071(4) 0.026(3) -0.013(3) 0.004(2) -0.005(3)
O6 0.3866(3) 0.4730(3) 0.0800(5) 0.0298(13) 0.020(3) 0.045(3) 0.025(3) -0.008(3) 0.000(2) 0.002(3)
O7 0.25 0.3731(4) 0.7068(8) 0.0276(17) 0.026(4) 0.032(4) 0.024(4) -0.008(3) 0 0
O8 0.3100(3) 0.4211(4) 0.8783(6) 0.0335(14) 0.018(3) 0.052(4) 0.030(3) -0.015(3) 0.001(2) -0.002(3)
O9 0.3792(4) 0.25 0.6935(9) 0.034(2) 0.026(4) 0.034(4) 0.043(5) 0 -0.016(4) 0
O10 0.4483(3) 0.3088(3) 0.8460(6) 0.0351(14) 0.040(3) 0.024(3) 0.042(4) 0.000(3) -0.020(3) 0.001(3)
O11 0.3970(5) 0.75 0.0941(9) 0.038(2) 0.031(5) 0.035(5) 0.049(6) 0 -0.001(4) 0
O12 0.5540(5) 0.75 0.8808(10) 0.042(2) 0.036(5) 0.039(5) 0.050(6) 0 0.007(4) 0
O13 0.25 0.3777(5) 0.1403(9) 0.039(2) 0.033(5) 0.038(5) 0.044(5) 0.003(4) 0 0
O14 0.25 0.5564(5) 0.0134(9) 0.035(2) 0.030(4) 0.033(5) 0.042(5) -0.001(4) 0 0
O15 0.3137(5) 0.75 0.5822(10) 0.045(4) 0.029(6) 0.058(8) 0.049(7) 0 -0.005(4) 0
O16 0.25 0.6690(18) 0.489(4) 0.082(16) 0.043(19) 0.08(3) 0.12(4) -0.02(3) 0 0
OH 0.25 0.6531(18) 0.628(4) 0.037(13) 0.028(18) 0.024(18) 0.06(3) -0.012(17) 0 0
OW1 0.3281(4) 0.5260(4) 0.5243(6) 0.0416(16) 0.047(4) 0.045(4) 0.033(3) -0.008(3) 0.001(3) 0.005(3)
OW2 0.4080(3) 0.4127(3) 0.6367(6) 0.0330(14) 0.035(3) 0.039(3) 0.025(3) -0.002(3) -0.002(2) -0.009(3)
OW3 0.25 0.6746(7) 0.2409(15) 0.084(4) 0.091(10) 0.052(7) 0.109(12) -0.016(7) 0 0
OW4 0.3994(5) 0.6575(4) 0.3744(7) 0.0533(19) 0.075(5) 0.055(4) 0.030(4) -0.009(3) 0.000(4) 0.013(4)
OW5 0.4729(7) 0.75 0.5764(15) 0.074(4) 0.057(7) 0.059(8) 0.105(11) 0 0.009(7) 0
OW6 0.4990(4) 0.5848(5) 0.5845(7) 0.061(2) 0.058(5) 0.077(6) 0.046(5) 0.026(4) 0.020(4) 0.030(4)
OW7 0.25 0.6261(7) 0.7475(13) 0.042(4) 0.033(6) 0.054(8) 0.040(8) 0.011(6) 0 0
OW8 0.25 0.75 0.9025(19) 0.067(5) 0.043(9) 0.068(11) 0.089(14) 0 0 0
OW9 0.25 0.25 0.9269(15) 0.063(5) 0.115(15) 0.032(7) 0.043(9) 0 0 0
OW10 0.6245(10) 0.6744(10) 0.6682(16) 0.120(9) 0.109(14) 0.158(17) 0.095(13) 0.008(11) 0.010(10) 0.026(12)
OW11 0.25 0.25 0.462(2) 0.075(11) 0.084(19) 0.10(3) 0.039(14) 0 0 0
OW12 0.25 0.174(3) 0.455(5) 0.09(2)
* Occupancies: C5, O16: 0.35(3); O15: 0.93(4); OH/OW7: 0.25/0.75(3); OW10: 0.75(3); OW11/OW12: 0.71/0.29(5)
Table 5. Selected bond distances (Å) for markeyite.
Ca1O8 2.360(5) U1O11 1.773(9) U2O14 1.768(9)
Ca1O1 2.368(5) U1O12 1.779(9) U2O13 1.773(9)
Ca1O4 2.369(6) U1O3(2) 2.411(5) U2O5(2) 2.416(6)
Ca1O10 2.383(6) U1O10(2) 2.427(6) U2O8(2) 2.436(6)
Ca1O2 2.399(5) U1O2(2) 2.481(5) U2O6(2) 2.457(5)
Ca1O6 2.404(6) <U1Oap> 1.776 <U2Oap> 1.771
Ca1OW2 2.494(6) <U1Oeq> 2.440 <U2Oeq> 2.436
<Ca1O> 2.397
C1O1 1.250(9) Hydrogen bonds
Ca2OH 2.279(5) C1O2 1.295(9) OW1···O5 2.717(9)
Ca2O15 2.343(5) C1O3 1.309(9) OW1···OH 2.93(3)
Ca2O3 2.384(6) <C1O> 1.285 OW2···O7 3.017(6)
Ca2OW1 2.428(7) OW2···O9 3.103(6)
Ca2OW6 2.450(7) C2O4 1.261(9) OW3···O11 3.334(12)
Ca2OW4 2.451(7) C2O5 1.296(9) OW4···O4 2.859(9)
Ca2O16 2.63(2) C2O6 1.301(9) OW6···O1 2.876(9)
Ca2O1 2.635(6) <C2O> 1.286 OW6···O4 2.896(9)
Ca2OW7 2.660(7) OW7···O14 2.981(16)
Ca2OW5 2.708(8) C3O7 1.258(13) OW8···O11 3.276(15)
<Ca2O>* 2.503 C3O8(2) 1.279(8) OW9···O13 3.197(17)
<C3O> 1.272 OW10···O12 2.861(19)
Ca3OW11(2) 2.24(3) OW10···O13 3.124(18)
Ca3O7(2) 2.286(8) C4O9 1.278(13)
Ca3O9(2) 2.324(8) C4O10(2) 1.294(8) Hydrogen bonds to
Ca3OW9 2.459(16) <C4O> 1.289 H2O groups are not
Ca3OW12(2) 2.71(6) included.
<Ca3O>* 2.347 C5O15(2) 1.250(13)
C5O16 1.33(2)
<C5O> 1.277
* Weighted average based on partial occupancies of OH, O15, O16, OW7, OW11 and OW12
sites; the effective coordination of Ca2 is 8.27 and that of Ca3 is 7.00.
Table 6. Bond valence analysis for markeyite. Values are expressed in valence units.*
Ca1
Ca2
Ca3
U1
U2
C1
C2
C3
C4
C5
hydrogen bonds
sum
O1
0.32
0.15
1.46
0.16
2.09
O2
0.29
0.44
2↓
1.29
2.02
O3
0.30
0.50
2↓
1.24
2.04
O4
0.32
1.42
0.16, 0.15
2.05
O5
0.49
2↓
1.29
0.22
2.00
O6
0.29
0.46
2↓
1.27
2.02
O7
0.40
2↓
1.43
0.13
1.96
O8
0.33
0.48
2↓
1.35
2↓
2.16
O9
0.36
2↓
1.36
0.11, 0.11
1.94
O10
0.30
0.48
2↓
1.30
2↓
2.08
O11
1.71
0.09, 0.09, 0.09
1.98
O12
1.69
0.16
1.85
O13
1.71
0.11, 0.10
1.92
O14
1.73
0.13
1.86
O15
0.34
0.93
0.49
1.46
2.29
O16
0.15
0.34↓
0.49
1.18
1.82
OH
0.41
2→
0.25↓
0.15, 0.15
1.12
OW1
0.27
Hydrogen bond
contributions
to OW sites and
bond-valence sums
for OW sites are
not included.
OW2
0.22
OW3
OW4
0.25
OW5
0.12
OW6
0.25
OW7
0.14
0.75↓
OW8
OW9
0.25
OW10
OW11
0.46
0.71
OW12
0.12
0.58
sum
2.07
1.92
2.17
6.24
6.29
4.00
3.98
4.13
3.95
4.10
* Multiplicity is indicated by . Bond strength contributions to Ca sites from partially occupied O
sites are adjusted for their occupancies. Ca2+O and C4+O bond valence parameters from Brown and
Altermatt (1985); U6+O bond valence parameters from Burns et al. (1997); hydrogen-bond strengths
based on OO bond lengths from Ferraris, G. and Ivaldi, G. (1988).
... Of the ten new species that the Markey mine has yielded, all contain uranyl and six contain carbonate; of the six new uranyl carbonates, five also contain essential Ca. The new mineral paramarkeyite, which is included in the aforementioned enumerations, is very closely related to three of the other new minerals from the Markey mine: markeyite (Kampf et al., 2018), natromarkeyite and pseudomarkeyite (Kampf et al., 2020a). ...
... It occurs on gypsum-coated asphaltum in association with andersonite, calcite, gypsum and natromarkeyite (Kampf et al., 2020a). Other new minerals recently described from the Markey mine are feynmanite (Kampf et al., 2019a), leószilárdite (Olds et al., 2017), magnesioleydetite (Kampf et al., 2019b), markeyite (Kampf et al., 2018), meyrowitzite (Kampf et al., 2019c), pseudomarkeyite (Kampf et al., 2020a), straβmannite (Kampf et al., 2019b) and uroxite (Kampf et al., 2020b). ...
... According to the correlation given by Libowitzky (1999), this corresponds to approximate O-H⋅⋅⋅O hydrogen bond-lengths between 3.2 and 2.7 Å, which is consistent with what is reported in the structures of markeyite and pseudomarkeyite. The broad bands in the 2800-2300 cm -1 range in the markeyite and pseudomarkeyite spectra were originally interpreted as corresponding to strong (short) hydrogen bonds (Kampf et al., 2018); however, no such bonds appear to exist in these structures and no such bands are seen in the paramarkeyite spectrum. We now think that these may be spectral artefacts because such bands have also been observed in spectra of anhydrous minerals, and we have recorded other spectra for markeyite that do not exhibit this feature. ...
Article
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 across. The mineral has white streak and vitreous lustre. It exhibits moderate bluish white fluorescence (405 nm laser). It is very brittle with irregular, curved fracture and a Mohs hardness of 2½. It has an excellent {100} cleavage and probably two good cleavages on {010} and {001}. The measured density is 2.91(2) g cm–3. Optically, the mineral is biaxial (–) with α = 1.550(2), β = 1.556(2), γ = 1.558(2) (white light); 2V = 60(2)°; strong r > v dispersion; orientation: Y = b; nonpleochroic. The Raman spectrum exhibits bands consistent with UO22+, CO32– and O–H. Electron microprobe analysis provided the empirical formula (Ca1.83Na0.20Sr0.03)∑2.05(UO2)(CO3)3·5H2O (+0.07 H). Paramarkeyite is monoclinic, P21/n, a = 17.9507(7), b = 18.1030(8), c = 18.3688(13) Å, β = 108.029(8)°, V = 5676.1(6) Å3 and Z = 16. The structure of paramarkeyite (R1 = 0.0647 for 6657 I > 2I) contains uranyl tricarbonate clusters that are linked by Ca–O polyhedra to form heteropolyhedral layers. The structure of paramarkeyite is very similar to those of markeyite, natromarkeyite and pseudomarkeyite.
... Meyrowitzite is a very rare mineral, found on calcite-veined asphaltum in association with gypsum, markeyite (Kampf et al. 2018), and rozenite. See Kampf et al. (2018) for a more complete list of the secondary minerals identified from the Markey mine, including several that are recently described new species. ...
... Meyrowitzite is a very rare mineral, found on calcite-veined asphaltum in association with gypsum, markeyite (Kampf et al. 2018), and rozenite. See Kampf et al. (2018) for a more complete list of the secondary minerals identified from the Markey mine, including several that are recently described new species. ...
Article
Meyrowitzite, Ca(UO 2)(CO 3) 2 ·5H 2 O, is a new mineral species from the Markey mine, Red Canyon, San Juan County, Utah, U.S.A. It is a secondary phase found on calcite-veined asphaltum in association with gypsum, markeyite, and rozenite. Meyrowitzite occurs as blades up to about 0.2 mm in length, elongate on [010], flattened on {100}, and exhibiting the forms {100}, {001}, {101}, {110}, and {011}. The mineral is yellow and transparent with vitreous luster and very pale yellow streak. Fluorescence under a 405 nm laser is from weak greenish yellow to moderate greenish blue. The Mohs hardness is ca. 2, tenacity is brittle, fracture is irregular, and there is one perfect cleavage, {101}. The measured density is 2.70(2) g/cm 3. The mineral is optically biaxial (+) with α = 1.520(2), β = 1.528(2), and γ = 1.561(2) (white light). The 2V(meas) = 53.0(6)°; weak dispersion, r > v; optical orientation: Z = b, Y ^ a ≈ 19° in obtuse β; pleochroism pale yellow, X ≈ Y < Z. Electron microprobe analyses provided the empirical formula Ca 0.94 (U 1.00 O 2)(CO 3) 2 ·5(H 2.02 O) on the basis of U = 1 and O = 13 apfu, as indicated by the crystal structure determination. Meyrowitzite is monoclinic, P2 1 /n, a = 12.376(3), b = 16.0867(14), c = 20.1340(17) Å, β = 107.679(13)°, V = 3819.3(12) Å 3 , and Z = 12. The structure (R 1 = 0.055 for 3559 I o > 2σI) contains both UO 7 pentagonal bipyramids and UO 8 hexagonal bipyramids, the latter participating in uranyl tricarbonate clusters (UTC). The two kinds of bipyramids and the carbonate groups link to form a novel corrugated heteropolyhedral sheet. This is the first structural characterization of a uranyl-carbonate mineral with a U:C ratio of 1:2. Meyrowitzite is apparently dimorphous with zellerite.
... Meyrowitzite is a very rare mineral, found on calcite-veined asphaltum in association with gypsum, markeyite ( Kampf et al. 2018), and rozenite. See Kampf et al. (2018) for a more complete list of the secondary minerals identified from the Markey mine, including several that are recently described new species. ...
... Meyrowitzite is a very rare mineral, found on calcite-veined asphaltum in association with gypsum, markeyite ( Kampf et al. 2018), and rozenite. See Kampf et al. (2018) for a more complete list of the secondary minerals identified from the Markey mine, including several that are recently described new species. ...
Preprint
Meyrowitzite, Ca(UO2)(CO3)2·5H2O, is a new mineral species from the Markey mine, Red Canyon, San Juan County, Utah, U.S.A. It is a secondary phase found on calcite-veined asphaltum in association with gypsum, markeyite, and rozenite. Meyrowitzite occurs as blades up to about 0.2 mm in length, elongate on [010], flattened on {100}, and exhibiting the forms {100}, {001}, {101}, {110}, and {011}. The mineral is yellow and transparent with vitreous luster and very pale yellow streak. Fluorescence is from weak greenish yellow to moderate greenish blue. The Mohs hardness is ca 2, tenacity is brittle, fracture is irregular, and there is one perfect cleavage, {-101}. The measured density is 2.70(2) g·cm-3. The mineral is optically biaxial (+) with α = 1.520(2), β = 1.528(2), and γ = 1.561(2) (white light). The 2V(meas.) = 53.0(6)°; weak dispersion, r > v; optical orientation: Z = b, Y ^ a ≈ 19° in obtuse β; pleochroism pale yellow, X ≈ Y < Z. Electron microprobe analyses provided the empirical formula Ca 0.94 (U 1.00 O 2)(CO 3) 2 ·5(H 2.02 O) on the basis of U = 1 and O = 13 apfu, as indicated by the crystal structure determination. Meyrowitzite is monoclinic, P2 1 /n, a = 31 12.376(3), b = 16.0867(14), c = 20.1340(17) Å, β = 107.679(13)°, V = 3819.3(12) Å 3 , and Z = 12. The structure (R 1 = 0.055 for 3559 I o > 2σI) contains both UO7 pentagonal bipyramids and UO8 hexagonal bipyramids, the later participating in uranyl tricarbonate clusters (UTC). The two kinds of bipyramids and the carbonate groups link to form a novel corrugated heteropolyhedral sheet. This is the first structural characterization of a uranyl-carbonate mineral with a U:C ratio of 1:2. Meyrowitzite is apparently dimorphous with zellerite.
... The first structurally characterized synthetic uranyl carbonate, to our knowledge, was one of the simplest phases 4a, sodiumbearing Na 4 (UO 2 )(CO 3 ) 3 [17]. It is of interest that the first crystal structure of the natural uranyl carbonate, rutherfordine (41), was reported the year before [85]. The papers of K. Mereiter from the TU Wien (Austria) should be certainly noted in the first row among the works devoted to the synthesis and structural studies of synthetic uranyl carbonates. ...
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Article
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 enriched by CO2, thus playing an important role in the release of U to the environment. The presence of uranyl carbonate phases has also been detected on the surface of “lavas” that were formed during the Chernobyl accident. It is of interest that with all the importance and prevalence of these phases, about a quarter of approved minerals still have undetermined crystal structures, and the number of synthetic phases for which the structures were determined is significantly inferior to structurally characterized natural uranyl carbonates. In this work, we review the crystal chemistry of natural and synthetic uranyl carbonate phases. The majority of synthetic analogs of minerals were obtained from aqueous solutions at room temperature, which directly points to the absence of specific environmental conditions (increased P or T) for the formation of natural uranyl carbonates. Uranyl carbonates do not have excellent topological diversity and are mainly composed of finite clusters with rigid structures. Thus the structural architecture of uranyl carbonates is largely governed by the interstitial cations and the hydration state of the compounds. The information content is usually higher for minerals than for synthetic compounds of similar or close chemical composition, which likely points to the higher stability and preferred architectures of natural compounds.
... Mezi jeho nejvýznamnější publikace patří práce "Infrared Spectroscopy and Thermal Analysis of the Uranyl Minerals", publikovaná v roce 1999 v prestižním Reviews in Mineralogy. (1996), vajdakit (2002), fosfowalpurgin (2004), pseudojohannit (2006), šreinit (2007), metarauchit (2008), běhounekit a sejkorait-(Y) (2011), adolfpaterait (2012), leydetit, meisserit, štěpit, švenekit a vysokýit (2013), geschieberit, mathesiusit, plášilit, a svornostit (2014), fermiit a ježekit (2015), tvrdýit (2016), alwilkinsit-(Y), gauthierit, klaprothit, línekit, ottohahnit, péligotit, plavnoit, rietveldit, shumwayit (2017), horákit, markeyit a nollmotzit (2018), šlikit, baumoit a vandermeerscheit (2019) ...
... Numerous other secondary minerals have been found at both mines (cf. Kampf et al., 2017 andKampf et al., 2018). ...
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Article
The new mineral feynmanite (IMA2017-035), Na(UO2)(SO4)(OH)·3.5H2O, was found in both the Blue Lizard and Markey mines, San Juan County, Utah, USA, where it occurs as a secondary phase on pyrite-rich asphaltum in association with chinleite-(Y), gypsum, goethite, natrojarosite, natrozippeite, plášilite, shumwayite (Blue Lizard) and wetherillite (Markey). The mineral is pale greenish yellow with white streak and fluoresces bright greenish white under a 405 nm laser. Crystals are transparent with vitreous luster. It is brittle, with Mohs hardness of ~2, irregular fracture and one perfect cleavage on {010}. The calculated density is 3.324 g cm-3. Crystals are thin needles or blades, flattened on {010} and elongate on [100], exhibiting the forms {010}, {001}, {101} and {10-1}, up to about 0.1 mm in length. Feynmanite is optically biaxial (–), α = 1.534(2), β = 1.561(2), γ = 1.571(2) (white light); 2Vmeas. = 62(2)°; no dispersion; optical orientation: X = b, Y ≈ a, Z ≈ c; and pleochroism: X colourless, Y very pale green yellow, Z pale green yellow (X < Y < Z). Electron microprobe analyses (WDS mode) provided (Na0.84Fe0.01)(U1.01O2)(S1.01O4)(OH)·3.5H2O. The five strongest X-ray powder diffraction lines are [dobs Å(I)(hkl)]: 8.37(100)(010), 6.37(33)(-101,101), 5.07(27)(-111,111), 4.053(46)(004,021) and 3.578(34)(120). Feynmanite is monoclinic, P2/n, a = 6.927(3), b = 8.355(4), c = 16.210(7) Å, β = 90.543(4)°, V = 938.1(7) Å3 and Z = 4. The structure of feynmanite (R1 = 0.0371 for 1879 Io > 2I) contains edge-sharing pairs of pentagonal bipyramids that are linked by sharing corners with SO4 groups, yielding a [(UO2)2(SO4)2(OH)2]2– sheet based on the phosphuranylite anion topology. The sheet is topologically identical to those in deliensite, johannite and plášilite. The dehydration of feynmanite to plášilite results in interlayer collapse involving geometric reconfiguration of the sheets and the ordering of Na.
... The Green Lizard mine is also a type locality for greenlizardite (Kampf et al., 2018b), shumwayite (Kampf et al., 2017b) and meitnerite (Kampf et al., 2018c). The Markey mine is also a type locality for feynmanite (Kampf et al., 2019), leószilárdite (Olds et al., 2017) and markeyite (Kampf et al., 2018a). ...
Article
Magnesioleydetite and straßmannite, two new uranyl sulfates minerals with sheet structures from Red Canyon, Utah - Anthony R. Kampf, Jakub Plášil, Anatoly V. Kasatkin, Barbara P. Nash, Joe Marty
Article
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 mm, pale yellow green colour; transparent; white streak; bright bluish white fluorescence (405 nm laser); vitreous to pearly lustre; brittle; Mohs hardness 1½ to 2; irregular fracture; three cleavages ({001} perfect, {100} and {010} good); density = 2.70(2) g cm-3 ; biaxial (-) with α = 1.528(2), β = 1.532(2) and γ = 1.533(2); and pleochroism is X = pale green yellow, Y ≈ Z = light green yellow. Pseudomarkeyite properties are: twinned tapering blades and tablets to 1 mm; pale green yellow colour; transparent; white streak; bright bluish white fluorescence (405 nm laser); vitreous to pearly lustre; brittle; Mohs hardness ≈ 1; stepped fracture; three cleavages ({10 1} very easy, {010} good, {100} fair); density = 2.88(2) g cm-3 ; biaxial (-) with α = 1.549(2), β = 1.553(2) and γ = 1.557(2); and it is nonpleochroic. The Raman spectra of markeyite, natromar-keyite and pseudomarkeyite are very similar and exhibit bands consistent with UO 2 2+ , CO 3 2-and O-H. Electron microprobe analyses provided the empirical formula Na 2.01 Ca 7.97 Mg 0.03 Cu 2+ 0.05 (UO 2) 4 (CO 3) 13 (H 2 O) 24 ⋅3H 2 O (-0.11 H) for natromarkeyite and Ca 7.95 (UO 2) 4 (CO 3) 12 (H 2 O) 18 ⋅3H 2 O (+0.10 H) for pseudomarkeyite. Natromarkeyite is orthorhombic, Pmmn, a = 17.8820(13), b = 18.3030(4), c = 10.2249(3) Å, V = 3336.6(3) Å 3 and Z = 2. Pseudomarkeyite is monoclinic, P2 1 /m, a = 17.531(3), b = 18.555(3), c = 9.130(3) Å, β = 103.95(3)°, V = 2882.3(13) Å 3 and Z = 2. The structures of natromarkeyite (R 1 = 0.0202 for 2898 I > 2σI) and pseudomarkeyite (R 1 = 0.0787 for 2106 I > 2σI) contain uranyl tricarbonate clusters that are linked by (Ca/Na)-O polyhedra forming thick corrugated heteropolyhedral layers. Natromarkeyite is isostructural with markeyite; pseudomarkeyite has a very similar structure.
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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, pale yellow-green colour; transparent; white streak; 2 bright bluish white fluorescence (405 nm laser); vitreous to pearly lustre; brittle; Mohs hardness 1½ to 2; irregular fracture; three cleavages ({001} perfect, {100} and {010} good); 2.70(2) g cm-3 density; biaxial (-) with α = 1.528(2), β = 1.532(2), γ = 1.533(2); pleochroism: X pale green yellow, Y ≈ Z light green yellow. Pseudomarkeyite properties: twinned tapering blades and tablets to 1 mm; pale green-yellow colour; transparent; white streak; bright bluish white fluorescence (405 nm laser); vitreous to pearly lustre; brittle; Mohs hardness ~1; stepped fracture; three cleavages ({10-1} very easy, {010} good, {100} fair); 2.88(2) g cm-3 density; biaxial (-) with α = 1.549(2), β = 1.553(2), γ = 1.557(2); nonpleochroic. The Raman spectra of markeyite, natromarkeyite and pseudomarkeyite are very similar and exhibit bands consistent with UO 2 2+ , CO 3 2-and O-H. Electron microprobe analyses provided the empirical formula Na 2.01 Ca 7.97 Mg 0.03 Cu 2+ 0.05 (UO 2) 4 (CO 3) 13 (H 2 O) 24 ·3H 2 O (-0.11 H) for natromarkeyite and Ca 7.95 (UO 2) 4 (CO 3) 12 (H 2 O) 18 ·3H 2 O (+0.10 H) for pseudomarkeyite. Natromarkeyite is orthorhombic, Pmmn, a = 17.8820(13), b = 18.3030(4), c = 10.2249(3) Å, V = 3336.6(3) Å^3 and Z = 2. Pseudomarkeyite is monoclinic, P2 1 /m, a = 17.531(3), b = 18.555(3), c = 9.130(3) Å, β = 103.95(3)°, V = 2882.3(13) Å^3 and Z = 2. The structures of natromarkeyite (R1 = 0.0202 for 2898 I > 2sigmaI) and pseudomarkeyite (R1 = 0.0787 for 2106 I > 2sigmaI) contain uranyl tricarbonate clusters that are linked by (Ca/Na)-O polyhedra forming thick corrugated heteropolyhedral layers. Natromarkeyite is isostructural with markeyite; pseudomarkeyite has a very similar structure.
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Na-Cu carbonates are relatively rare secondary minerals in weathering zones of ore deposits. Hereby we describe mineral composition and crystal chemistry of the most important secondary (Na)Cu minerals and their Na-and Mg-bearing associates forming rich paragenesis in Rudna IX mine. A non-bulky Ca-rich dripstone-like paragenesis from Lubin Główny mine is also characterized, using Powder X-Ray Diffraction, Rietveld, and Electron Microprobe methods. Light blue juangodoyite (3rd occurrence worldwide) and darker chalconatronite are the most important members of the Rudna IX paragenesis, being associated with malachite, aragonite (intergrown with hydromagnesite and northupite), and probably cornwallite. Most of the minerals are chemically close to their ideal composition, with minor Mg substitution in malachite. Cu chlorides are mainly represented by clinoatacamite and probably herbertsmithite. Additional, minor phases include trace Cu minerals langite, wroewolfeite, and a lavendulan-group mineral, and monohydrocalcite. Separate halite-rich encrustations are shown to be filled with eriochalcite, ktenasite, and kröhnkite. The most likely to be confirmed coexisting species include paratacamite, wooldridgeite/nesquehonite, johillerite, melanothallite, and kipushite. The Lubin paragenesis mainly comprises aragonite, gypsum, rapidcreekite, and monohydrocalcite, with trace vaterite. Blue colouration is mainly provided by a yet unspecified Ni-, Co-, Mg-, and Mn-bearing Cu-Zn-Ca arsenate mineral close to parnauite.
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Abstract The total valence of the bonds between acceptors and the H atoms bonded to a water molecule (s d) is taken equal to the bond valence (st) received by the donor 0 atom from coordination bonds. For an OH- group, s d = sr-l. Plots of the bond valence s for H...O bonds as functions of O...O, H...O and O-H distances are fitted with the function s = (R/Ro)-b+ k. The most reliable fitting is obtained for s vs O...O; a minimum value of O...O ~_2.55 A for the hydrogen bonds donated by a water molecule is predicted. Similar curves from the literature are compared and discussed.
Article
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 about 2½ and exhibit bright bluish-green fluorescence, and all are easily soluble in RT H2O. Only klaprothite exhibits cleavage; perfect on {100} and {001}. Quantitative EDS analyses yielded the empirical formulas Na6.01(U 26 1.03O2)(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, P-1, 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, P-1, 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 link clusters 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-Melchior Péligot (1811–1890) and Otto Hahn (1879–1968).
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Diffractometry has been used with monochromatic Mo K/sub /alpha// radiation, /Theta//2/Theta/ method, full-matrix least-squares refinement in the anisotropic approximation, spherical single crystal 0.21 mm in diameter, and R factor on all 1570 reflections 0.028 in a refinement of the crystal structure for CsâNpOâClâ. The compound is monoclinic: a = 1.5435 (6), b = 1.2796 (5), c = 0.7306 (3) nm, /gamma/ = 117.23 (5)/degree/, space group B2/b. Bond lengths: Np-20 0.1828 (5), Np-Cl⁠0.2759 (3), Np-Clâ 0.2758(3). The Np-O bond characteristics have been compared for NpOâ/sup 2+/ and NpOâ/sup +/. It is concluded that there is marked reduction in the interaction between the equatorial and axial bonds in NpO/sup +/â by comparison with NpOâ/sup 2+/.
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The Gladstone–Dale relationship allows one to derive a compatibility index of the physical and chemical data used to characterize a mineral. Minerals of the following groups are reviewed: carbonates, sulfates, phosphates, vanadates, vanadium oxysalts, chromates, molybdates, tungstates, germanates, iodates, nitrates, oxalates, antimonites, antimonates, sulfites, halides, and borates. The mineral species in the Fair, Poor and Incomplete categories in these groups require further study.
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Parameters for the calculation of bond valence (s) from bond length (r) have been determined for 750 atom pairs using the Inorganic Crystal Structure Database. In the relation s = exp((ro - r)/B), it is found that B = 0.37 was consistent with most of the refined values and the 141 most accurate values of ro for this value of B are tabulated. An algorithm for the calculation of ro in terms of position of the two atoms in the periodic table is given. Graphical bond-valence-bond-length correlations are presented for hydrogen bonds.-J.E.C.