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Author(s):  
Anthony R. Kampf ◽  
Aaron J. Celestian ◽  
Barbara P. Nash ◽  
Joe Marty

ABSTRACT The new minerals allantoin (IMA2020–004a), C4H6N4O3, and natrosulfatourea (IMA2019–134), Na2(SO4)[CO(NH2)2], were found in the Rowley mine, Maricopa County, Arizona, USA, where they occur together in bat guano in association with aphthitalite and urea. Allantoin properties: colorless, transparent, untwinned blades to 0.3 mm; white streak; vitreous luster; brittle; Mohs hardness 1½; conchoidal fracture; good {100} cleavage; 1.72(2) g/cm3 density; biaxial (+) with α = 1.558(2), β = 1.593(2), γ = 1.715(3); 2V = 60(1)°; slight r > v dispersion; optical orientation: Y = b, Z ^ a = 30° in obtuse β. Natrosulfatourea properties: colorless, transparent, untwinned prisms to 0.3 mm; white streak; vitreous luster; brittle; Mohs hardness 1½; irregular fracture; perfect {100} cleavage; 1.97(2) g/cm3 density; biaxial (+) with α = 1.456(2), β = 1.464(5), γ = 1.524(2); 2V = 42(1)°; no dispersion; optical orientation: X = a, Y = c, Z = b. Quantitative chemical analyses could not be obtained for allantoin. Electron microprobe analyses provided the empirical formula Na2.02(S0.98O4)[CO(NH2)2] for natrosulfatourea. Allantoin is monoclinic, P21/c, a = 8.0304(9), b = 5.1596(5), c = 14.8011(18) Å, β = 93.017(7)°, V = 612.41(11) Å3, and Z = 4. Natrosufatourea is orthorhombic, Pbcn, a = 5.5918(4), b = 18.1814(14), c = 6.7179(5) Å, V = 682.98(9) Å3, and Z = 4. The crystal structure of allantoin (R1 = 0.0432 for 1073 I > 2σI) is the same as that reported for the equivalent organic compound. In the structure of natrosulfatourea (R1 = 0.0413 for 785 I > 2σI) NaO6 polyhedra and SO4 tetrahedra form polyhedral layers. The O atom of the CO(NH2)2 (urea) group ligates to two Na atoms and projects into the space between polyhedral layers, linking adjacent layers through hydrogen bonds.


2021 ◽  
Vol 71 ◽  
pp. 75-99
Author(s):  
Evan S. H. Quah ◽  
L. Lee Grismer ◽  
Perry L. Wood Jr. ◽  
Kelvin K. P. Lim ◽  
Paul Y. Imbun ◽  
...  

The taxonomic status of the ranid frog Abavorana luctuosa (Peters, 1871) was investigated using a combination of molecular and morphological data. The analyses revealed that A. luctuosasensu lato is composed of two species in Borneo. One of these species agrees with the description of Rana decorata Mocquard, 1890 which is resurrected in the combination Abavorana decoratacomb. nov. (Mocquard, 1890). Abavorana decorata is recovered as the sister lineage to the remainder of Abavorana and differs by a 16.0–17.0 % uncorrected pairwise sequence divergence from its congeners A. nazgul and A. luctuosa, respectively. It is distinguishable morphologically from A. luctuosa and A. nazgul by its ventral pattern (bold, black and white reticulations on its venter along with bold banding on the underside of hind limbs vs. generally immaculate and spotted in the latter two species), and a prominent white streak beneath the eye and/or tympanum extending to the corner of the jaw. Abavorana decorata further differs from A. luctuosa by having a significantly wider head and snout, larger interorbital and tympanum diameters, longer femur in both sexes, and various combinations of other mensural characters. Both species are sympatric in Borneo and this discovery adds to a growing number of widespread Sundaic species shown to be species complexes with distinct forms in Borneo.


2020 ◽  
Vol 84 (5) ◽  
pp. 753-765 ◽  
Author(s):  
Anthony R. Kampf ◽  
Travis A. Olds ◽  
Jakub Plášil ◽  
Peter C. Burns ◽  
Joe Marty

AbstractThe new minerals natromarkeyite, Na2Ca8(UO2)4(CO3)13(H2O)24⋅3H2O (IMA2018-152) and pseudomarkeyite, Ca8(UO2)4(CO3)12(H2O)18⋅3H2O (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$\bar{1}$} 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, natromarkeyite and pseudomarkeyite are very similar and exhibit bands consistent with UO22+, CO32– and O–H. Electron microprobe analyses provided the empirical formula Na2.01Ca7.97Mg0.03Cu2+0.05(UO2)4(CO3)13(H2O)24⋅3H2O (–0.11 H) for natromarkeyite and Ca7.95(UO2)4(CO3)12(H2O)18⋅3H2O (+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) Å3 and Z = 2. Pseudomarkeyite is monoclinic, P21/m, a = 17.531(3), b = 18.555(3), c = 9.130(3) Å, β = 103.95(3)°, V = 2882.3(13) Å3 and Z = 2. The structures of natromarkeyite (R1 = 0.0202 for 2898 I > 2σI) and pseudomarkeyite (R1 = 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.


2020 ◽  
Vol 69 (6) ◽  
pp. 1060-1069
Author(s):  
Wardatou Boukari ◽  
Denis Filloux ◽  
Jean Heinrich Daugrois ◽  
Emmanuel Fernandez ◽  
Dimitre Mollov ◽  
...  

2019 ◽  
Vol 84 (2) ◽  
pp. 267-273
Author(s):  
Anthony R. Kampf ◽  
Barbara P. Nash ◽  
Arturo A. Molina Donoso

AbstractThe new mineral mauriziodiniite (IMA2019-036), NH4(As2O3)2I, was found at the Torrecillas mine, Iquique Province, Chile, where it is a secondary alteration phase associated with calcite, cuatrocapaite-(NH4), lavendulan, magnesiokoritnigite and torrecillasite on matrix consisting of native arsenic, arsenolite and pyrite. Mauriziodiniite occurs as hexagonal tablets up to ~300 μm in diameter. Crystals are colourless and transparent, with pearly to adamantine lustre and white streak. The Mohs hardness is ~1. Tablets are sectile and easily flexible, but not elastic. Fracture is curved, irregular and stepped. Cleavage is perfect on {001}. The calculated density is 3.916 g/cm3. Optically, mauriziodiniite is uniaxial (–) with ω = 2.07(calc) and ɛ = 1.770(5) (white light). The empirical formula, determined from electron microprobe analyses, is (NH4)0.94K0.03(As2O3)2I0.92Cl0.03. Mauriziodiniite is hexagonal, P6/mmm, a = 5.289(2), c = 9.317(2) Å, V = 225.68(18) Å3 and Z = 1. The structure, refined to R1 = 4.16% for 135 Io > 2σI reflections, contains three types of layers: (1) a planar neutral As2O3 (arsenite) sheet; (2) an NH4+ layer that links adjacent arsenite sheets via bonds to their O atoms; and (3) an I– layer that links adjacent arsenite sheets via bonds to their As atoms. The layer sequence is I–As2O3–NH4–As2O3–I. Mauriziodiniite is isostructural with lucabindiite and is structurally related to gajardoite, cuatrocapaite-(NH4), cuatrocapaite-(K) and torrecillasite.


Minerals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 219
Author(s):  
Victor Yakovenchuk ◽  
Yakov Pakhomovsky ◽  
Taras Panikorovskii ◽  
Andrey Zolotarev ◽  
Julia Mikhailova ◽  
...  

Chirvinskyite, (Na,Ca)13(Fe,Mn,□)2(Ti,Nb)2(Zr,Ti)3(Si2O7)4(OH,O,F)12, is a new wöhlerite–related zirconotitano–sorosilicate. It is triclinic, P1, a = 7.0477(5), b = 9.8725(5), c = 12.2204(9) Å, α = 77.995(5), β = 82.057(6), γ = 89.988(5)°, V = 823.35(9) Å3, Z = 1. The mineral was found in albitized alkaline pegmatites in a foyaite of the Mt. Takhtarvumchorr (Khibiny alkaline massif, Kola Peninsula, Russia, N 67°40’, E 33°33’). Chirvinskyite forms sheaf–like and radiated aggregates (up to 6 mm in diameter) of split fibrous crystals hosted by saccharoidal fluorapatite and albite. The mineral is pale cream in color, with a silky luster and a white streak. The cleavage is not recognized. Mohs hardness is 5. Chirvinskyite is biaxial (–), α 1.670(2), β 1.690(2), γ 1.705(2) (589 nm), 2Vcalc = 80.9°. The calculated and measured densities are 3.41 and 3.07(2) g·cm−3, respectively. The empirical formula based on Si = 8 apfu is (Na9.81Ca3.28K0.01)∑13.10(Fe0.72Mn0.69□0.54Mg0.05)∑2.00 (Ti1.81Nb0.19)∑2.00(Zr2.27Ti0.63)∑2.90(Si2O7)4{(OH)5.94O3.09F2.97}∑12.00. Chirvinskyite belongs to a new structure type of minerals and inorganic compounds and is related to the wöhlerite-group minerals. Its modular “wallpaper” structure consists of disilicate groups Si2O7 and three types of “octahedral walls”. The mineral is named in honor of Petr Nikolaevich Chirvinsky (1880–1955), Russian geologist and petrographer, head of the Petrography Department of the Perm’ State University (1943–1953), for his contributions to mineralogy and petrology, including studies of the Khibiny alkaline massif.


2018 ◽  
Vol 83 (03) ◽  
pp. 349-360 ◽  
Author(s):  
Anthony R. Kampf ◽  
Jakub Plášil ◽  
Anatoly V. Kasatkin ◽  
Barbara P. Nash ◽  
Joe Marty

AbstractMagnesioleydetite (IMA2017-063), Mg(UO2)(SO4)2·11H2O, and straβmannite (IMA2017-086), Al(UO2)(SO4)2F·16H2O, are two new minerals from mines in Red Canyon, San Juan County, Utah, USA. Magnesioleydetite occurs in the Markey mine and straβmannite occurs in both the Markey and Green Lizard mines. Both minerals are secondary phases found in efflorescent crusts on the surfaces of mine walls. Magnesioleydetite occurs in irregular aggregates (to ~0.5 mm) of blades (to ~0.2 mm) exhibiting the following properties: transparent to translucent; pale green–yellow colour; vitreous lustre; white streak; non-fluorescent; brittle; Mohs hardness ≈ 2; irregular fracture; one perfect cleavage on {001}; and calculated density = 2.463 g/cm3. Straβmannite occurs in irregular aggregates (to ~0.5 mm) of equant crystals (to ~0.2 mm) exhibiting the following properties: transparent; light yellow–green colour; vitreous to greasy lustre; nearly white streak; bright greenish-blue fluorescence; somewhat brittle, Mohs hardness ≈ 1½; irregular fracture; one good cleavage on {001}; measured and calculated densities of 2.20(2) and 2.173 g/cm3, respectively; optically biaxial (–); α = 1.477(2), β = 1.485(2) and γ = 1.489(2) (white light); 2Vmeas.= 72(2)°; dispersionr>v(slight); orientationY=b,X∧c= 20° (in obtuse β); pleochroism withX= nearly colourless,Y= pale green–yellow andZ= light green–yellow (X<Y<Z). The empirical formulas for magnesioleydetite and straβmannite are (Mg0.56Fe0.26Zn0.11Mn0.01)Σ0.94(U0.99O2)(S1.015O4)2·11H2O and Al1.00Na0.16(U0.99O2)(S1.00O4)2[F0.58(OH)0.42]·16H2O, respectively. Magnesioleydetite is monoclinic,C2/c,a= 11.3513(3),b= 7.7310(2),c= 21.7957(15) Å, β = 102.387(7)°,V= 1868.19(16) Å3andZ= 4. Straβmannite is monoclinic,C2/c,a= 11.0187(5),b= 8.3284(3),c= 26.6727(19) Å, β = 97.426(7)°,V= 2427.2(2) andZ= 4. The structures of magnesioleydetite (R1= 0.016 for 2040I> 2σIreflections) and straβmannite (R1= 0.0343 for 2220I> 2σIreflections) each contain uranyl-sulfate sheets based on the protasite-anion topology.


2015 ◽  
Vol 79 (5) ◽  
pp. 1123-1142 ◽  
Author(s):  
Anthony R. Kampf ◽  
Jakub Plášil ◽  
Anatoly V. Kasatkin ◽  
Joe Marty ◽  
Jiří Čejka

AbstractThe new minerals fermiite (IMA2014-068), Na4(UO2)(SO4)3·3H2O and oppenheimerite (IMA2014-073), Na2(UO2)(SO4)2·3H2O, were found in the Blue Lizard mine, San Juan County, Utah, USA, where they occur together as secondary alteration phases in association with blödite, bluelizardite, chalcanthite, epsomite, gypsum, hexahydrite, kröhnkite, manganoblödite, sideronatrite, tamarugite and wetherillite.Fermiite descriptive details: pale greenish-yellow prisms; transparent; vitreous lustre; bright greenishwhite fluorescence; white streak; hardness (Mohs) 2½; brittle; conchoidal fracture; no cleavage; slightly deliquescent; easily soluble in RT H2O; densitymeas = 3.23(2) g cm–3; densitycalc = 3.313 g cm–3. Optically, biaxial (+), α = 1.527(1), β = 1.534(1), γ = 1.567(1) (white light); 2Vmeas.= 51(1)°, 2Vcalc.= 50°; dispersionr<v, distinct. Pleochroism:X,Y= colourless,Z= pale greenish yellow;X=Y<Z. Energy dispersive spectroscopic (EDS) analyses yielded the empirical formula Na3.88(U1.05O2)(S0.99O4)3(H2O)3. Fermiite is orthorhombic,Pmn21,a= 11.8407(12),b= 7.8695(5),c= 15.3255(19) Å,V= 1428.0(2) Å3andZ= 4. The structure (R1= 2.21% for 1951Io> 3σI) contains [(UO2)(SO4)3] chains that are linked by bonds involving five different Na–O polyhedra to form a framework. The mineral is named for Italian-American theoretical and experimental physicist Dr. Enrico Fermi (1901–1954).Oppenheimerite descriptive details: pale greenish-yellow prisms; transparent; vitreous lustre; bright greenish-white fluorescence; white streak; hardness (Mohs) 2½; slightly sectile; three good cleavages, {110}, {011} and {101}; irregular fracture; slightly deliquescent; easily soluble in RT H2O; densitycalc = 3.360 g cm–3. Optically, biaxial (+), α = 1.537(1), β = 1.555(1), γ = 1.594(1) (white light); 2Vmeas.= 72(2)°, 2Vcalc.= 70°; dispersion isr>v, moderate, inclined; optical orientation:X≈ ⊥ {101},Z≈ [111]; pleochroism: X very pale greenish yellow, Y pale greenish yellow, Z greenish yellow; X < Y < Z. EDS analyses yielded the empirical formula Na1.94(U0.97O2)(S1.02O4)2(H2O)3. Oppenheimerite is triclinic,P1,a= 7.9576(6),b= 8.1952(6),c= 9.8051(7) Å, α = 65.967(5), β = 70.281(5), γ = 84.516(6)°,V= 549.10(8) Å3andZ= 2. The structure (R1= 3.07% for 2337Io> 3σI) contains [(UO2)(SO4)2(H2O)] chains that are linked by bonds involving two different Na–O polyhedra to form a framework. The mineral is named for American theoretical physicist Dr. J. Robert Oppenheimer (1904–1967).


2015 ◽  
Vol 79 (5) ◽  
pp. 1203-1211 ◽  
Author(s):  
R. W. Turner ◽  
O. I. Siidra ◽  
M. S. Rumsey ◽  
Y. S. Polekhovsky ◽  
Y. L. Kretser ◽  
...  

AbstractYeomanite, Pb2O(OH)Cl, is a new Pb-oxychloride found in the manganese pod mineral assemblage at Merehead (Torr Works) Quarry, near Cranmore, Somerset, England. Yeomanite is named in joint recognition of Mrs Angela Yeoman (1931–) and her company, Foster Yeoman, who operated Merehead Quarry for aggregate until 2006. The mineral is normally white, occasionally grey, with a white streak and a vitreous to transparent lustre. Invariably intimately associated with mendipite, yeomanite appears to be formed of small, twisted, rope-like fibres growing from the end of columnar mendipite masses, forming loose mats and strands resembling asbestos. Individual fibres are generally <8 mm long, but exceptionally may reach up to 15 mm. There is a perfect cleavage parallel to the long axis of the fibres but this is masked by the fibrous nature, especially as individual fibres break easily. The Dcalc for the ideal formula is 7.303 g/cm3. The mean RI in air at 589 nm is 2.27. The eight strongest reflections in the powder X-ray diffraction pattern [(d in Å) (Intensity) (hkl)] are: 2.880(100)(113); 2.802(78)(006); 3.293(61)(200); 3.770(32)(011); 2.166(22)(206); 1.662(19)(119); 2.050(18)(303); 3.054(17)(105) Yeomanite is orthorhombic, Pnma, a = 6.585(10), b = 3.855(6), c = 17.26(1) Å, V = 438(1) Å3, Z = 4. Yeomanite is a new example of the growing family of lead oxychloride minerals that have a structure based upon oxocentred OPb4 tetrahedra, which, in this mineral, jointly with OHPb3 triangles, form [O(OH)Pb2]+ chains similar to those observed in synthetic Pb2O(OH)I. Yeomanite is structurally related to sidpietersite, penfieldite and laurionite.


2015 ◽  
Vol 79 (2) ◽  
pp. 413-423 ◽  
Author(s):  
D. Nishio-Hamane ◽  
M. Ohnishi ◽  
K. Momma ◽  
N. Shimobayashi ◽  
R. Miyawaki ◽  
...  

AbstractImayoshiite, Ca3Al(CO3)[B(OH)4](OH)6·12H2O, occurs in cavities in the altered gabbro xenolith in the sepentinized dunite exposed at Suisho-dani, Ise City, Mie Prefecture, Japan. Imayoshiite is colourless and transparent with a vitreous lustre and its aggregates are white with a silky lustre. Imayoshiite has a white streak. Its Mohs hardness is 2–3. It is brittle, the cleavage is distinct on {100} and the fracture is uneven. The mineral is uniaxial (–) with the indices of refraction ω = 1.497(2) and ε = 1.470(2) in white light. Imayoshiite is hexagonal, P63, a = 11.0264(11), c = 10.6052(16) Å by powder diffraction and a = 11.04592(2), c = 10.61502(19) Å by single-crystal diffraction. The structural refinement converged to R1 = 2.35%. Imayoshiite is the first member of the ettringite group with both CO3 and B(OH)4 anions.


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