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Tomiolloite (IMA2021-019) is a new aluminum tellurite sulfite-sulfate mineral discovered at the Bambolla mine, Moctezuma, Sonora, Mexico, a well-known tellurium (Te) mineral locality. Tomiolloite forms roughly spherical clusters of crystals comprised of very thin, needle-like crystals (1 μm diameter, ~40 μm length) around a core of small, stubbier, broken crystals. Tomiolloite is generally found growing on tellurite or quartz. The strongest powder X‑ray diffraction lines are [dobsÅ (Iobs) (hkl)]: 11.667 (89) (100), 8.240 (38) (101), 4.107 (29) (202,211,121), 3.223 (100) (203,302,130), and 2.905 (37) (213,123,222,400). The empirical formula of tomiolloite, as determined by electron microprobe analysis, is (Al10.64Te61.01+Fe30.31+Zn0.04)Σ12(Te45.00+Pb0.02)Σ5.02(S40.49+S60.49+Si0.02)Σ1.00O21.53[(OH)20.86Cl0.11]Σ20.97, which is simplified to the ideal formula Al12(Te4+O3)5[(SO3)0.5(SO4)0.5](OH)24. Significant Te6+substitution for Al3+is observed in tomiolloite, verified by X‑ray photoelectron spectroscopy and crystal-structure analysis. The structure of tomiolloite was determined using synchrotron single-crystal X‑ray diffraction, showing that tomiolloite is hexagonal and crystallizes in the space-group P63/m, with the unit-cell parameters a= 13.3360(19) Å, c= 11.604(2) Å, V= 1787.3(6) Å3, and Z = 2. Tomiolloite has a unique microporous framework structure, which bears a slight similarity to that of zemannite, but it has a much larger cavity diameter (8.85 Å). The framework is built from edge-sharing Mφ6octahedra (M= Al3+and Te6+), Te4+O3trigonal pyramids, and Te4+O4disphenoids. Mφ6octahedra edge-share to form crankshaft-shaped chains along c, with Te4+Onpolyhedra filling notches in the crankshafts and providing linkages between adjacent chains. The framework has an overall positive charge, which is balanced by the presence of both sulfite (SO32−) trigonal pyramids and sulfate (SO42−) tetrahedra in the channels.

For four decades fairbankite was reported to have the formula Pb2+(Te4+O3), but repeated attempts to isolate fairbankite crystals for structural determination found only the visually similar cerussite and, more rarely, anglesite. The crystal-structure determination of fairbankite using single-crystal X‑ray diffraction, supported by electron microprobe analysis and X‑ray powder diffraction on the type specimen, has shown that fairbankite contains essential S, along with Pb, Te, and O. The chemical formula of fairbankite has been revised to Pb122+Te4+O311SO4.$\mathrm{Pb}_{12}^{2+}\left(\mathrm{Te}^{4+} \mathrm{O}_{3}\right)_{11}\left(\mathrm{SO}_{4}\right).$This change has been accepted by the IMA–CNMNC, Proposal 19-I. The crystal structure of fairbankite [space group P1 (no. 1); revised cell: a= 7.0205(3) Å, b= 10.6828(6) Å, c= 14.4916(8) Å, a = 75.161(5)°, b = 81.571(4)°, g = 83.744(4)°, V= 1036.35(9) Å3, and Z= 1] is the first atomic arrangement known to contain a Te34+O96−$\mathrm{Te}_{3}^{4+} \mathrm{O}_{9}^{6-}$non-cyclic, finite building unit. Fairbankite has an average structure, formed from a 3D framework of Pb2+Onpolyhedra, Te4+Onpolyhedra, and SO4tetrahedra in a 12:11:1 ratio. The stereoactive lone pairs of the Pb2+and Te4+cations are oriented into void space within the structure. Fairbankite contains two mixed sites statistically occupied by Te4+and S6+in approximately 4:1 and 1:4 ratios. These two sites possess Te4+in trigonal-pyramidal environment and S6+in tetrahedral environment (with an additional O site to create tetrahedral SO4shape for the S-dominant site). Six of the 10 fully occupied Te4+sites have Te4+in trigonal-pyramidal environment, while four have Te4+at the center of highly distorted Te4+O4disphenoids. The disphenoids allow for the creation of two dimeric Te24+O64−$\mathrm{Te}_{2}^{4+} \mathrm{O}_{6}^{4-}$units in addition to the Te34+O96−$\mathrm{Te}_{3}^{4+} \mathrm{O}_{9}^{6-}$trimeric unit, which contains two disphenoids. All linkage between disphenoids and trigonal pyramids is via corner-linking. Secondary connectivity is via long Te–O and Pb–O bonds.

The classification and nomenclature of mineral species is regulated by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA-CNMNC). This mineral species classification is necessary for Earth Sciences, as minerals constitute most planetary and interstellar materials. Hazen (2019)has proposed a classification of minerals and other Earth and planetary materials according to “natural clustering.” Although this classification is complementary to the IMA-CNMNC mineral classification and is described as such, there are some unjustified criticisms and factual errors in the comparison of the two schemes. It is the intent of the present comment to (1) clarify the use of classification schemes for Earth and planetary materials, and (2) counter erroneous criticisms or statements about the current IMA-CNMNC system of approving proposals for new mineral species and classifications.

Tellurium (Te) is a Critical Element that is toxic to microorganisms and humans alike, most notably in its soluble oxyanionic forms. To date, the biogeochemical behaviour of Te in Earth’s surface environment is largely unknown. Here, we report the discovery of elemental Te nanoparticles (Te NPs) in regolith samples using Single-Particle Inductively Coupled Plasma Mass Spectroscopy. Tellurium NPs were detected in both proximal and distal locations (bulk concentrations >4 ppm) relative to weathering Te ores. Synchrotron X-ray Fluorescence Mapping and X-ray Absorption Spectroscopy showed that bulk Te in the regolith is generally associated with Fe (oxyhydr)oxides and clay minerals, and mostly found in the oxidation states +IV and +VI. Although Te NPs account for less than 2 mol‰ of Te in our samples, their detection provides evidence for the active biogeochemical cycling of Te in surface environments. Te NPs are reactive and are likely to have formed in situ in distal samples, most likely via microbially-mediated reduction. Hence, the presence of Te NPs indicates the potential for release of toxic soluble forms of Te even in environments where most Te is “fixed” in forms such as Fe (oxyhydr)oxides that have low solubility and poor bioavailability.

Apexite (IMA2015-002), NaMg(PO4)·9H2O, is a new mineral from the Apex mine, Lander County, Nevada, U.S.A., where it occurs as a low-temperature secondary mineral on massive quartz matrix in association with andersonite, calcite, čejkaite, gaylussite, and goethite. Apexite forms colorless needles up to 0.5 mm in length. The streak is white. Crystals are transparent and have vitreous to satiny luster. The Mohs hardness is about 2, the tenacity is brittle, the fracture is curved, and crystals exhibit one perfect cleavage on {100}. The measured density is 1.74(1) g/cm3and the calculated density is 1.741 g/cm3. Electron microprobe analyses provided: Na2O 9.26, MgO 14.42, P2O523.31, H2O 53.01 (structure), total 100.00 wt% (normalized). The empirical formula (based on 13 O apfu) is: Na0.91Mg1.09P1.00O13.00H17.91. Apexite is triclinic, P1̄, a = 6.9296(7), b = 11.9767(13), c = 14.9436(19) Å, α = 92.109(6), β = 102.884(7), γ = 105.171(7)°, V = 1160.9(2) Å3, and Z = 4. The eight strongest lines in the X‑ray powder diffraction pattern are [dobsin Å(I)(hkl)]: 14.63(35)(001); 5.11(61)(021,1̅1̅1,110,1̅20); 4.68(75)(02̅2,1̅1̅2,12̅1,01̅3); 4.301(96)(102,013,022,1̅13); 4.008(44) (1̅1̅3,12̅2); 2.876(46)(040); 2.762(100)(2̅1̅3,23̅1,03̅4,2̅04,015); and 2.507(30)(212,025,2̅2̅3). Apexite is a new struvite-type phase with a unique structure (R1= 4.44% for 1401 Fo> 4σF) consisting of four components: (1) a [Na2Mg4(H2O)14]10+heteropolyhedral cation cluster; (2) a trans edge-sharing chain of Na(H2O)6octahedra; (3) an isolated PO4group; and (4) an isolated H2O group. The structural components are linked to one another only via hydrogen bonds. Its structure is related to that of hazenite.

A sample of Sb-rich segnitite from the Black Pine mine, Montana, U.S.A., has been studied by microprobe analyses, single-crystal X-ray diffraction, and μ-EXAFS and XANES spectroscopy. Linear combination fitting of the spectroscopic data provided Sb5+:Sb3+= 85(2):15(2), where Sb5+is in octahedral coordination substituting for Fe3+and Sb3+is in tetrahedral coordination substituting for As5+. Based upon this Sb5+:Sb3+ratio, the microprobe analyses yielded the empirical formula Pb1.02H1.02(Fe3+2.36Sb5+0.41Cu2+0.27)Σ3.04(As5+1.78Sb3+0.07S6+0.02)Σ1.88O8(OH)6.00. The crystal structure refinement and bond valence analysis are consistent with these cation site assignments. The formation of Sb-rich segnitite opens new possibilities for Sb sinks within the supergene zone. Segnitite may, in fact, be an ideal host for the sequestering of several toxic elements for pH < 2. At higher pH values, As is more likely to be incorporated into schwertmannite and ferrihydrite.

The new mineral graţianite, MnBi2S4, is described from the Bǎiţa Bihor skarn deposit, Bihor County, Romania. Graţianite occurs as thin lamellae, intimately intergrown with cosalite and bismuthinite, or as flower-shaped blebs within chalcopyrite, where it is associated with cosalite and tetradymite. Graţianite displays weak to modest bireflectance in air and oil, respectively, and strong anisotropy. The mean empirical composition based on 20 electron probe microanalyses is: (Mn0.541Fe0.319Pb0.070Cu0.040Cd0.009Ag0.001)S0.980(Bi1.975Sb0.018)S1.993(S4.008Se0.012Te0.007)S4.027, corresponding to the ideal formula MnBi2S4. Graţianite crystallizes in the monoclinic system (space group C2/m). Single-crystal X-ray studies of material extracted by the focused ion beam-scanning electron microscopy (FIB-SEM) technique, and carried out on the MX2 macromolecular beamline of the Australian Synchrotron determined the following cell dimensions: a = 12.6774(25) Å, b = 3.9140(8) Å, c = 14.7581(30) Å, b = 115.31(3)°, V = 662.0(2) Å3, and Z = 4. The six strongest X-ray reflections and their relative intensities are: 3.448 Å (100), 2.731 Å (77), 2.855 Å (64), 3.637 Å (55), 3.644 Å (54), and 3.062 Å (51).

Single-crystal diffraction of jarosite, KFe33+(SO4)2(OH)6, has been undertaken at low temperatures that proxy for martian surface conditions. Room-temperature data are consistent with literature data [a = 7.2913(5), c = 17.1744(17), and V = 790.72(11) in R3¯m], while the first low-temperature data for the mineral is presented (at 253, 213, 173, and 133 K). Data collections between 297 and 133 K show strongly anisotropic thermal expansion, with the c axis much more expandable than the a axis. Much of the anisotropy is due to strong distortion of the KO12polyhedron, which increases by 8% between 297 and 133 K. The data sets can aid in the identification of jarosite by X-ray diffraction of martian soils using the Curiosity Rover’s CheMin instrument.

Eckhardite, (Ca,Pb)Cu2+Te6+O5(H2O), is a new tellurate mineral from Otto Mountain near Baker, California, U.S.A. It occurs in vugs in quartz in association with Br-rich chlorargyrite, gold, housleyite, khinite, markcooperite, and ottoite. It is interpreted as having formed from the partial oxidation of primary sulfides and tellurides during or following brecciation of quartz veins. Eckhardite is monoclinic, space group P21/n, with unit-cell dimensions a = 8.1606(8), b = 5.3076(6), c = 11.4412(15) Å, ß = 101.549(7)°, V = 485.52(10) Å3, and Z = 4. It forms as needles or blades up to about 150 × 15 × 5 mm in size, typically in radial or sub-radial aggregates, but also as isolated needles. The color is light bluish green and the streak is very pale bluish green. Crystals are transparent with vitreous to subadamantine luster. The Mohs hardness is estimated at between 2 and 3. Eckhardite is brittle with an irregular fracture and one likely (but not observed) cleavage on {101}. The calculated density based on the empirical formula is 4.644 g/cm3. The mineral is biaxial (-), with indices of refraction of a = 1. 770 (calc), ß = 1.860 (calc), and ? = 1.895(5). The measured 2V is 61.2(5)°, dispersion is r < v, perceptible and the optical orientation is Z = b; X ˜ [101]. The pleochroism is: Z (light blue green) < Y (very pale blue green) < X (colorless). The normalized electron microprobe analyses (average of 4) provided: PbO 4.79, CaO 15.90, MgO 0.06, CuO 22.74, Fe2O30.06, TeO351.01, H2O 5.45 (structure), total 100 wt%. The empirical formula (based on 6 O apfu) is: Ca0.962Pb0.073Cu2+0.971Mg0.005Fe3+0.002Te6+0.986O6H2.052. The Raman spectrum exhibits prominent features consistent with the mineral being a tellurate, as well as an OH stretching feature confirming a hydrous component. The eight strongest powder X-ray diffraction lines are [dobsin Å (hkl) I]: 5.94 (101) 100, 3.287 (112) 80, 2.645 (020,2¯13) 89, 2.485 (1¯14,301,014) 48, 2.245 (114,122) 46, 1.809 (223,4¯13,321,4¯04) 40, 1.522 (413,5¯12,421,133) 42, and 1.53 (2¯17,2¯33,4¯06) 43. The crystal structure of eckhardite (R1= 0.046 for 586 reflections with Fo> 4sF) consists of stair-step-like octahedral layers of Te6+O6and Cu2+O6octahedra parallel to {101}, which are linked in the [101¯] direction by bonds to interlayer Ca atoms. The structure can be described as a stacking of stepped HCP layers alternating with chains of CaO7polyhedra. The structures of bairdite, timroseite, and paratimroseite also contain stair-step-like HCP polyhedral layers.

Bairdite, Pb2Cu42+Te26+O10(OH)2(SO4)(H2O), is a new tellurate-sulfate from Otto Mountain near Baker, California, U.S.A. It occurs in vugs in quartz associated with khinite, cerussite, goethite, and hematite. It is interpreted as having formed from the partial oxidation of primary sulfides and tellurides during or following brecciation of quartz veins. Bairdite is monoclinic, space group P21/c, with unit-cell dimensions a = 14.3126(10), b = 5.2267(3), c = 9.4878(5) Å, b = 106.815(7)°, V = 679.41(7) Å3, and Z = 2. Bairdite occurs as diamond-shaped tabular crystals up to about 250 mm long and 5 mm thick, in subparallel and fan-shaped aggregates. The color is lime green, the streak is pale lime green, and the luster is adamantine. The Mohs hardness is estimated at between 2 and 3. Bairdite is brittle with an irregular fracture and one perfect cleavage on {100}. The calculated density based on the empirical formula is 6.062 g/cm3. Bairdite is biaxial (+), with calculated indices of refraction of a = 1.953, b = 1.966, and g = 2.039. The measured 2V is 47(2)°, dispersion is r < v, strong and the optical orientation is Y = b; Z ^ a = 34° in obtuse angle b. The pleochroism is strong: Z (pale green) <<< X (green) < Y (green). Electron microprobe analyses (average of 4) provided: PbO 34.22, CaO 0.06, CuO 23.80, TeO326.34, SO35.74, H2O 2.81 (structure), total 92.97 wt%. The empirical formula (based on 17 O atoms pfu) is: Pb2.05Ca0.01Cu2+3.99Te6+2.00S0.96O17.00H4.16. The eight strongest powder X-ray diffraction lines are [dobsin Å (hkl) I]: 4.77 (110,102) 50, 4.522 (002,011,111) 66, 3.48 (multiple) 62, 2.999 (311,411) 97, 2.701 (502,113,213) 79, 2.614 (013,020) 100, 1.727 (multiple) 65, and 1.509 (911,033,324) 83. The crystal structure of bairdite (R1= 0.072 for 1406 reflections with Fo> 4sF) contains edge-sharing chains of Te6+O6and Cu2+O6octahedra parallel to b that are joined by corner-sharing in the a direction, forming thick stair-step-like hexagonal close packed layers parallel to {100}. The polyhedral sheet has similarities to those in the structures of timroseite and paratimroseite. The thick interlayer region contains PbO10polyhedra and half-occupied SO4groups. Raman and infrared spectral data are presented

Fuettererite, Pb3Cu62+Te6+O6(OH)7Cl5, is a new tellurate from Otto Mountain near Baker, California, named for Otto Fuetterer who is largely responsible for the development of the mining claims on Otto Mountain. The new mineral is known from only two specimens, one from the NE2 vein and the other from the Bird Nest drift. Fuettererite occurs in vugs in quartz, on the first specimen associated with Br-rich chlorargyrite, iodargyrite, and telluroperite and on the second specimen associated with anglesite, anatacamite, atacamite, chalcopyrite, galena, goethite, hematite, muscovite, phosphohedyphane, timroseite, and wulfenite. It is interpreted as having formed from the partial oxidation of primary sulfides and tellurides during or following brecciation of quartz veins. Fuettererite is hexagonal, with space group R3¯, a = 8.4035(12), c = 44.681(4) Å, V = 2732.6(6) Å3, and Z = 6. Crystals are tabular to short prismatic, exhibit the forms {100}, {101}, and {001} and reach a maximum dimension of 50 µm. The color is bluish green, the streak is pale bluish-green, and the luster is adamantine. The Mohs hardness is estimated at between 2 and 3. The new mineral is brittle with irregular fracture and one perfect cleavage on {001}. The calculated density based on the empirical formula is 5.528 g/ cm3. Fuettererite is uniaxial (-), with calculated indices of refraction of ? = 2.04 and e = 1.97, and is dichroic bluish-green, E < O. Electron microprobe analysis provided: PbO 41.45, CuO 30.35, Al2O30.23, TeO312.80, Cl 12.08, H2O 3.55 (structure), O=Cl -2.73, total 97.73 wt%. The empirical formula (based on 18 O + Cl apfu) is: Pb2.88Cu2+5.92Al0.07Te6+1.13O6.59(OH)6.12Cl5.29. The ten strongest powder X-ray diffraction lines are [dobsin Å (hkl) I]: 6.106 (104) 44, 3.733 (0.0.12) 100, 2.749 (121¯) 53, 2.6686 (124¯) 49, 2.5289 (127¯) 41, 2.2772 (1.2.11) 38, 1.9637 (315, 1.2.1¯6¯) 87, 1.8999 (multiple) 48, 1.5976 (multiple) 40, and 1.5843 (410, 1.2.23, 143) 44. The crystal structure of fuettererite (R1= 0.031 for 971 reflections with Fo > 4sF) contains edge-sharing sheets of CuO5Cl and TeO6octahedra. These sheets are virtually identical to that in the structure of spangolite, but in fuettererite they are linked together to form a double sheet. The double octahedral sheets alternate with thick double layers of PbO2Cl6polyhedra. The CuO5Cl octahedra exhibit pronounced Jahn-Teller distortions and the PbO2Cl6polyhedron has a lopsided distribution of bond lengths attributable to the localization of the Pb2+6s2lone-pair electrons.

Agaite, Pb3Cu2+Te6+O5(OH)2(CO3), is a new tellurate from the Aga mine on Otto Mountain near Baker, California, U.S.A. The new mineral is known from only one specimen. It occurs on quartz in association with cerussite, Br-rich chlorargyrite, chrysocolla, goethite, khinite, markcooperite, muscovite, phosphohedyphane, timroseite, and wulfenite. It is interpreted as having formed from the partial oxidation of primary sulfides and tellurides during or following brecciation of quartz veins. Agaite is orthorhombic, space group Pca21, with unit-cell dimensions a = 10.6522(7), b = 9.1630(5), c = 9.6011(7) Å, V = 937.12(11) Å3, and Z = 4. Agaite crystals form as blades flattened on {010} and probably elongated on [001], and are up to about 20 µm thick and 200 µm in length. The color is blue, the streak is pale blue, and the luster is adamantine. The Mohs hardness is estimated at between 2 and 3. Agaite is brittle with an irregular fracture and one perfect cleavage on {010}. The calculated density based on the empirical formula is 6.987 g/cm3. Agaite is biaxial (-), with calculated indices of refraction of a = 2.015, ß = 2.065, and ? = 2.070°. The measured 2V is 34(5)° and the optical orientation is X = b, Y = c, and Z = a. It is pleochroic: X = pale blue, Y and Z = blue; X < Y = Z. Electron microprobe analyses (average of 4) provided: PbO 65.91, CuO 7.75, TeO317.41, CO24.33 (structure), H2O 1.78 (structure), total 97.18 wt%. The empirical formula (based on 10 O apfu) is: Pb3.00Cu2+0.99Te6+1.01O5(OH)2(CO3). The eight strongest powder X-ray diffraction lines are [dobsin Å (hkl) I]: 4.26 (012) 28, 4.165 (211) 14, 3.303 (022, 310, 221) 100, 2.7472 (131, 203, 312) 68, 2.571 (032, 401, 231) 14, 2.0814 (332, 422) 21, 2.0306 (511) 17, and 1.7468 (multiple) 40. The crystal structure of agaite (R1= 0.033 for 1913 reflections with Fo > 4sF) contains edge-sharing chains of Cu2+O5square pyramids and Te6+O6octahedra parallel to a that are joined by corner-sharing in the c direction, forming a polyhedral sheet parallel to {010}. The polyhedral sheet is very similar to those in the structures of timroseite and paratimroseite. The thick interlayer region contains 8- and 9-coordinated Pb2+, as well as CO3and OH groups. The Pb coordinations have lopsided distributions of bond lengths attributable to the localization of the Pb2+6s2lone-pair electrons.

Saltonseaite, K3NaMn2+Cl6, is a new mineral from the Salton Sea, Imperial County, California, U.S.A., which formed as the result of the evaporation of geothermal (hydrothermal) brines enriched in K, Na, Mn, and Cl. It occurs as lozenge-shaped and bladed crystals to about 10 cm that are composites of parallel-grown {012} rhombohedra. It is associated with large, well-formed crystals of sylvite and halite. Crystals are transparent and colorless, but appear light orange due to inclusions of akaganéite. The streak is white and the luster is vitreous to oily, the latter being due to deliquescence. The Mohs hardness is about 2½, the tenacity is brittle, the fracture is irregular, and crystals exhibit one very good cleavage on {110}. The mineral has an astringent taste and is markedly hygroscopic. The measured and calculated densities are 2.26(1) and 2.297 g/cm3, respectively. Saltonseaite is soluble in water at room temperature and crystallizes from solution above 52 °C. Optically, saltonseaite is uniaxial positive, with ? = 1.577(1) and e = 1.578(1) (white light) and is non-pleochroic. Energy-dispersive spectroscopic analyses (average of 5) provided: K 28.79, Na 5.35, Mn 13.48, Fe 0.24, Cl 52.19, total 100.05 wt%. The empirical formula (based on 6 Cl atoms) is: K3.00Na0.95Mn2+1.00Fe2+0.02Cl6. Saltonseaite is trigonal, R3¯c, with cell parameters a = 12.0966(5), c = 13.9555(10) Å, V = 1768.48(16) Å3, and Z = 6. The nine strongest lines in the X-ray powder diffraction pattern are [dobs in Å(I)(hkl)]: 5.83(61) (012); 3.498(25)(300); 2.851(68)(131); 2.689(32)(312); 2.625(62)(214); 2.542(100)(223); 1.983(32) (324); 1.749(20)(600), and 1.384(22)(multiple). The structure of saltonseaite (R1= 1.08% for 558 Fo> 4sF) contains face-sharing chains of alternating Mn2+Cl6octahedra and NaCl6polyhedra along c. The chains are joined via bonds to eight-coordinated K atoms. Saltonseaite is isostructural with rinneite, K3NaFe2+Cl6, and very similar in structure with chlormanganokalite, K4Mn2+Cl6. Existing chemical analyses for saltonseaite and rinneite fail to confirm a solid-solution series between them; experimental studies are needed.

The new mineral whelanite, Cu2Ca6[Si6O17(OH)](CO3)(OH)3(H2O)2, was approved by the Commission on New Minerals and Mineral Names (IMA) in 1977, but until now a description has not been published. The mineral is orthorhombic with space group Pn2n and cell parameters a = 5.6551(4), b = 3.683(3), c = 27.1372(7) Å, V = 565.3(5) Å3, and Z = 1. The mineral occurs with thaumasite, stringhamite, and kinoite in a copper-rich, diopside-garnet-magnetite skarn at the Bawana mine, Beaver County, Utah, and has also been confirmed to occur at other localities. At the Bawana mine, it is found as irregular clusters and radial aggregates of platy to lath-like crystals up to 1 mm in length, flattened on {001} and elongated on [100]. The color and streak are pale blue and the luster is vitreous. The laths are flexible, but not elastic. Cleavage is perfect on {001} and good on {010}, producing splintery fracture. The Mohs’ hardness is about 2½. The measured density is 2.74(3) g/cm3and the calculated density is 2.737 g/cm3based upon the empirical formula. The mineral is biaxial (-), α = 1.612(2), β = 1.622(calc), and γ = 1.626(2), and 2Vmeas= 64(1)°. The pleochroism is weak: X = Y (pale blue) < Z (light blue). The optical orientation is X = a, Y = c, Z = b. A combination of electron microprobe analyses and thermogravimetric analyses (for CO2and H2O) yielded: CaO 34.46, CuO 12.09, FeO 1.52, SiO237.96, CO25.93, H2O 8.86, total 100.82 wt%, providing the empirical formula (based on O = 26):

The new mineral reynoldsite, Pb2Mn4+2O5(CrO4), occurs at the Blue Bell claims, near Baker, San Bernardino County, California, U.S.A., and at the Red Lead mine, Dundas, Tasmania, Australia. At the Blue Bell claims, reynoldsite occurs in subparallel growths and divergent sprays of thin prisms with a square cross section. At the Red Lead mine, it occurs as thin rectangular blades. At both occurrences, crystals are small (≤0.2 mm), and ubiquitously and multiply twinned. At both deposits, reynoldsite formed as a secondary mineral derived from the weathering of primary minerals including oxides and sulfides in the presence of acidic groundwater. Reynoldsite is dark orange-brown to black in color and has a dark orange-brown streak. Its luster is subadamantine and its Mohs hardness is about 4½. The mineral is brittle with irregular to splintery fracture and a poorly developed {001} cleavage. The calculated density is 6.574 g/cm3(Red Lead mine). The very high indices of refraction and dark color permitted only partial determination of the transmitted light optical properties. Electron microprobe analyses of Blue Bell and Red Lead reynoldsite provided the empirical formulas (based on nine O atoms): Pb1.97Mn2.01O5(Cr1.01O4) and (Pb2.07Sr0.04)Σ2.11Mn2.15O5(Cr0.87O4), respectively. The strongest powder X-ray diffraction lines for Red Lead reynoldsite are [d(hkl)I]: 3.427(02̅1,110)52, 3.254(021,11̅2,12̅1)85, 3.052(1̅ 1̅2,111,02̅2,1̅03)100, 2.923(013,1̅22)40, 2.5015(004,2̅11,1̅30)47, 1.9818(01̅5,1̅05,202,23̅1)42, 1.7694(1̅15,13̅4,203,1̅42,1̅ 3̅3)36, and 1.6368(2̅2̅3,04̅3,221,124,22̅4)36. Reynoldsite is triclinic with space group P1 and unit-cell parameters: a = 5.0278(7), b = 7.5865(11), c = 10.2808(15) Å, α = 91.968(12), β = 99.405(12), γ = 109.159(10)°, V = 363.81(9) Å3, and Z = 2 (for a Red Lead mine crystal). The crystal structure of reynoldsite (R1= 10.2% for 902 reflections with Fo > 4σF for a Red Lead crystal) contains close-packed layers of edge-sharing Mn4+O6octahedra parallel to {001}. These layers are composed of edge-sharing double chains of octahedra extending along [100], which in turn are linked to one another by sharing edges in the [010] direction. The thick interlayer region contains Pb2+cations and CrO4tetrahedra. The 6s2lone-electron pair of the Pb2+is stereochemically active, resulting in a one-sided Pb-O coordination arrangement. The structure bears strong similarities to those of the phyllomanganates, such as chalcophanite and birnessite.

Chromschieffelinite, Pb10Te6O20(OH)14(CrO4)(H2O)5, is a new tellurate from Otto Mountain near Baker, California, named as the chromate analog of schieffelinite, Pb10Te6O20(OH)14(SO4)(H2O)5. The new mineral occurs in a single 1 mm vug in a quartz vein. Associated mineral species include: chalcopyrite, chrysocolla, galena, goethite, hematite, khinite, pyrite, and wulfenite. Chromschieffelinite is orthorhombic, space group C2221, a = 9.6646(3), b = 19.4962(8), c = 10.5101(7) Å, V = 1980.33(17) Å3, and Z = 2. Crystals are blocky to tabular on {010} with striations parallel to [001]. The forms observed are {010}, {210}, {120}, {150}, {180}, {212}, and {101}, and crystals reach 0.2 mm in maximum dimension. The color and streak are pale yellow and the luster is adamantine. The Mohs hardness is estimated at 2. The new mineral is brittle with irregular fracture and one perfect cleavage on {010}. The calculated density based on the ideal formula is 5.892 g/cm3. Chromschieffelinite is biaxial (-) with indices of refraction α = 1.930(5), β = 1.960(5), and γ = 1.975(5), measured in white light. The measured 2V is 68(2)°, the dispersion is strong, r < v, and the optical orientation is X = b, Y = c, Z = a. No pleochroism was observed. Electron microprobe analysis provided: PbO 59.42, TeO329.08, CrO31.86, H2O 6.63 (structure), total 96.99 wt%; the empirical formula (based on 6 Te) is Pb9.65Te6O19.96(OH)14.04(CrO4)0.67(H2O)6.32. The strongest powder X-ray diffraction lines are [dobsin Å (hkl) I]: 9.814 (020) 100, 3.575 (042,202) 41, 3.347 (222) 44, 3.262 (241,060,113) 53, 3.052 (311) 45, 2.9455 (152,133) 55, 2.0396 (115,353) 33, and 1.6500 (multiple) 33. The crystal structures of schieffelinite (R1= 0.0282) and chromschieffelinite (R1= 0.0277) contain isolated Te6+O6octahedra and Te26+O11corner-sharing dimers, which are linked into a three-dimensional framework via bonds to Pb2+atoms. The framework has large channels along c, which contain disordered SO4or CrO4groups and H2O. The lone-electron pair of each Pb2+is stereochemically active, resulting in one-sided Pb-O coordination arrangements. The short Pb-O bonds of the Pb2+coordinations are all to Te6+O6octahedra, resulting in strongly bonded layers parallel to {010}, which accounts for the perfect {010} cleavage.

A new occurrence of rankamaite is here described at the Urubu pegmatite, Itinga municipality, Minas Gerais, Brazil. The mineral forms cream-white botryoidal aggregates of acicular to fibrous crystals, intimately associated with simpsonite, thoreaulite, cassiterite, quartz, elbaite, albite, and muscovite. The average of six chemical analyses obtained by electron microprobe is (range in parentheses, wt%): Na2O 2.08 (1.95-2.13), K2O 2.61 (2.52-2.74), Al2O31.96 (1.89-2.00), Fe2O30.01 (0.00-0.03), TiO20.02 (0.00-0.06), Ta2O581.04 (79.12-85.18), Nb2O59.49 (8.58-9.86), total 97.21 (95.95-101.50). The chemical formula derived from this analysis is (Na1.55K1.28)Σ2.83(Ta8.45Nb1.64Al0.89Fe3+0.01Ti0.01)Σ11.00[O25.02(OH)5.98]Σ31.00. Rankamaite is an orthorhombic “tungsten bronze” (OTB), crystallizing in the space group Cmmm. Its unit-cell parameters refined from X‑ray diffraction powder data are: a = 17.224(3), b = 17.687(3), c = 3.9361(7) Å, V = 1199.1(3) Å3, Z = 2. Rietveld refinement of the powder data was undertaken using the structure of LaTa5O14as a starting model for the rankamaite structure. The structural formula obtained with the Rietveld analyses is: (Na2.21K1.26)Σ3.37(Ta9.12Nb1.30Al0.59)Σ11.00[O26.29(OH)4.71]Σ31.00. The tantalum atoms are coordinated by six and seven oxygen atoms in the form of distorted TaO6octahedra and TaO7pentagonal bipyramids, respectively. Every pentagonal bipyramid shares edges with four octahedra, thus forming Ta5O14units. The potassium atom is in an 11-fold coordination, whereas one sodium atom is in a 10-fold and the other is in a 12-fold coordination. Raman and infrared spectroscopy were used to investigate the room-temperature spectra of rankamaite.

Yttriaite-(Y), ideally Y2O3, is a new mineral (IMA2010-039) from the alluvial deposits of the Bol’shaya Pol’ya River, Subpolar Urals, Russia. The new mineral occurs as isolated crystals, typically cubo-octahedra <6 μm in size, embedded in massive native tungsten. Associated minerals include: copper, zircon, osmium, gold, and pyrite. The main forms observed are {100} and {111}. Due to the crystal size, physical properties could not be determined; however, the properties of synthetic Y2O3are well known. Synthetic Y2O3crystals are colorless to white with a white streak; crystals are transparent with an adamantine luster, while massive Y2O3is typically translucent with an earthy luster. Synthetic Y2O3has a Vickers hardness of 653.91, which corresponds to 5.5 on the Mohs scale. Synthetic Y2O3crystals have good cleavage on {111}. Yttriaite-(Y) is isotropic; the refractive index measured at 587 nm on synthetic Y2O3is n = 1.931. The empirical chemical formula (mean of 4 electron microprobe analyses) calculated on the basis of 3 O is: Y1.98Dy0.01Yb0.01O3. Yttriaite-(Y) is cubic, space group Ia3̅, with parameters a = 10.6018(7) Å, V = 1191.62(7) Å3, and Z = 16. The five strongest lines in the powder X-ray diffraction pattern (measured on synthetic Y2O3using synchrotron radiation) are [dobsin Å (I) (hkl)]: 3.0646 (100) (222), 1.8746 (55) (440), 1.5984 (38) (622), 2.6537 (26) (400), and 4.3356 (14) (211). The mineral name is based on the common name for the chemical compound, yttria.

Stichtite, ideally Mg6Cr2CO3(OH)16∙4H2O, from Stichtite Hill, Tasmania, Australia, and barbertonite, also ideally Mg6Cr2CO3(OH)16∙4H2O, from the Kaapsehoop asbestos mine, South Africa, have been studied by powder X-ray diffraction and their structures have been refined using the Rietveld method. Stichtite from Stichtite Hill crystallizes in the rhombohedral space group R3̄m, with unitcell parameters a = 3.09575(3) and c = 23.5069(6) Å, V = 195.099(6) Å3, with Z = 3/8. Barbertonite from the Kaapsehoop asbestos mine crystallizes in the hexagonal space group P63/mmc. The co-type specimens of barbertonite were found to be intergrown mixtures consisting of barbertonite and stichtite. Unit-cell parameters of barbertonite from the co-type specimens were a = 3.09689(6), c = 15.6193(8) Å, and V = 129.731(8) Å3and a = 3.09646(6), c = 15.627(1) Å V = 129.76(1) Å3, and Z = ¼. Rietveld refinements of both stichtite and barbertonite show that they are polytypes rather than polymorphs and do not represent distinct mineral species. Several possible nomenclature systems are discussed for the naming of hydrotalcite minerals and groups. Raman band assignments are also presented for stichtite from Stichtite Hill.

Telluroperite, Pb3Te4+O4Cl2, is a new tellurite from Otto Mountain near Baker, California. The new mineral occurs on fracture surfaces and in small vugs in brecciated quartz veins in direct association with acanthite, bromine-rich chlorargyrite, caledonite, cerussite, galena, goethite, and linarite. Various other secondary minerals occur in the veins, including six new tellurates, housleyite, markcooperite, paratimroseite, ottoite, thorneite, and timroseite. Telluroperite is orthorhombic, space group Bmmb, a = 5.5649(6), b = 5.5565(6), c = 12.4750(14) Å, V = 386.37(7) Å3, and Z = 2. The new mineral occurs as rounded square tablets and flakes up to 0.25 mm on edge and 0.02 mm thick. The form {001} is prominent and is probably bounded by {100}, {010}, and {110}. It is bluish-green and transparent, with a pale bluish-green streak and adamantine luster. The mineral is non-fluorescent. Mohs hardness is estimated to be between 2 and 3. The mineral is brittle, with a curved fracture and perfect {001} cleavage. The calculated density based on the empirical formula is 7.323 g/cm3. Telluroperite is biaxial (-), with very small 2V (~10°). The average index of refraction is 2.219 calculated by the Gladstone-Dale relationship. The optical orientation is X = c and the mineral exhibits moderate bluish-green pleochrosim; absorption: X < Y = Z. Electron microprobe analysis provided PbO 72.70, TeO219.26, Cl 9.44, O≡Cl -2.31, total 99.27 wt%. The empirical formula (based on O+Cl = 6) is Pb2.79Te4+1.03O3.72Cl2.28. The six strongest powder X-ray diffraction lines are [dobsin Å (hkl) I]: 3.750 (111) 58, 2.857 (113) 100, 2.781 (020, 200) 43, 2.075 (024, 204) 31, 1.966 (220) 30, and 1.620 (117, 313, 133) 52. The crystal structure (R1= 0.056) is based on the Sillén X1structure-type and consists of a three-dimensional structural topology with lead-oxide halide polyhedra linked to tellurium/lead oxide groups. The mineral is named for the relationship to perite and the dominance of Te (with Pb) in the Bi site of perite.

Timroseite, Pb2Cu52+(Te6+O6)2(OH)2, and paratimroseite, Pb2Cu42+(Te6+O6)2(H2O)2, are two new tellurates from Otto Mountain near Baker, California. Timroseite is named in honor of Timothy (Tim) P. Rose and paratimroseite is named for its relationship to timroseite. Both new minerals occur on fracture surfaces and in small vugs in brecciated quartz veins. Timroseite is directly associated with acanthite, cerussite, bromine-rich chlorargyrite, chrysocolla, gold, housleyite, iodargyrite, khinite-4O, markcooperite, ottoite, paratimroseite, thorneite, vauquelinite, and wulfenite. Paratimroseite is directly associated with calcite, cerussite, housleyite, khinite-4O, markcooperite, and timroseite. Timroseite is orthorhombic, space group P21nm, a = 5.2000(2), b = 9.6225(4), c = 11.5340(5) Å, V = 577.13(4) Å3, and Z = 2. Paratimroseite is orthorhombic, space group P212121, a = 5.1943(4), b = 9.6198(10), c = 11.6746(11) Å, V = 583.35(9) Å3, and Z = 2. Timroseite commonly occurs as olive to lime green, irregular, rounded masses and rarely in crystals as dark olive green, equant rhombs, and diamond-shaped plates in subparallel sheaf-like aggregates. It has a very pale yellowish green streak, dull to adamantine luster, a hardness of about 2½ (Mohs), brittle tenacity, irregular fracture, no cleavage, and a calculated density of 6.981 g/cm3. Paratimroseite occurs as vibrant “neon” green blades typically intergrown in irregular clusters and as lime green botryoids. It has a very pale green streak, dull to adamantine luster, a hardness of about 3 (Mohs), brittle tenacity, irregular fracture, good {001} cleavage, and a calculated density of 6.556 g/cm3. Timroseite is biaxial (+) with a large 2V, indices of refraction > 2, orientation X = b, Y = a, Z = c and pleochroism: X = greenish yellow, Y = yellowish green, Z = dark green (Z > Y > X). Paratimroseite is biaxial (-) with a large 2V, indices of refraction > 2, orientation X = c, Y = b, Z = a and pleochroism: X = light green, Y = green, Z = green (Y = Z >> X). Electron microprobe analysis of timroseite provided PbO 35.85, CuO 29.57, TeO327.75, Cl 0.04, H2O 1.38 (structure), O≡Cl -0.01, total 94.58 wt%; the empirical formula (based on O+Cl = 14) is Pb2.07Cu2+4.80Te6+2.04O12(OH)1.98Cl0.02. Electron microprobe analysis of paratimroseite provided PbO 36.11, CuO 26.27, TeO329.80, Cl 0.04, H2O 3.01 (structure), O≡Cl -0.01, total 95.22 wt%; the empirical formula (based on O+Cl = 14) is Pb1.94Cu2+3.96Te6+2.03O12(H2O)1.99Cl0.01. The strongest powder X-ray diffraction lines for timroseite are [dobsin Å (hkl) I]: 3.693 (022) 43, 3.578 (112) 44, 3.008 (023) 84, 2.950 (113) 88, 2.732 (130) 100, 1.785 (multiple) 33, 1.475 (332) 36; and for paratimroseite 4.771 (101) 76, 4.463 (021) 32, 3.544 (120) 44, 3.029 (023,122) 100, 2.973 (113) 48, 2.665 (131) 41, 2.469 (114) 40, 2.246 (221) 34. The crystal structures of timroseite (R1 = 0.029) and paratimroseite (R1= 0.039) are very closely related. The structures are based upon edge- and corner-sharing sheets of Te and Cu polyhedra parallel to (001) and the sheets in both structures are identical in topology and virtually identical in geometry. In timroseite, the sheets are joined to one another along c by sharing the apical O atoms of Cu octahedra, as well as by sharing edges and corners with an additional CuO5square pyramid located between the sheets. The sheets in paratimroseite are joined only via Pb-O and H bonds.

Markcooperite, Pb2(UO2)Te6+O6, is a new tellurate from Otto Mountain near Baker, California, named in honor of Mark A. Cooper of the University of Manitoba for his contributions to mineralogy. The new mineral occurs on fracture surfaces and in small vugs in brecciated quartz veins. Markcooperite is directly associated with bromian chlorargyrite, iodargyrite, khinite-4O, wulfenite, and four other new tellurates: housleyite, thorneite, ottoite, and timroseite. Various other secondary minerals occur in the veins, including two other new secondary tellurium minerals: paratimroseite and telluroperite. Markcooperite is monoclinic, space group P21/c, a = 5.722(2), b = 7.7478(2), c = 7.889(2) Å, β = 90.833(5)°, V = 349.7(2) Å3, and Z = 2. It occurs as pseudotetragonal prisms to 0.2 mm with the forms {100} and {011} and as botryoidal intergrowths to 0.3 mm in diameter; no twinning was observed. Markcooperite is orange and transparent, with a light orange streak and adamantine luster, and is non-fluorescent. Mohs hardness is estimated at 3. The mineral is brittle, with an irregular fracture and perfect {100} cleavage. The calculated density is 8.496 g/cm3based on the empirical formula. Markcooperite is biaxial (+), with indices of refraction α = 2.11, β = 2.12, γ = 2.29 calculated using the Gladstone-Dale relationship, measured α-β birefringence of 0.01 and measured 2V of 30(5)°. The optical orientation is X = c, Y = b, Z = a. The mineral is slightly pleochroic in shades of orange, with absorption: X > Y = Z. No dispersion was observed. Electron microprobe analysis provided PbO 50.07, TeO322.64, UO325.01, Cl 0.03, O≡Cl -0.01, total 97.74 wt%; the empirical formula (based on O+Cl = 8) is Pb2.05U0.80Te6+1.18O7.99Cl0.01. The strongest powder X-ray diffraction lines are [dobsin Å (hkl) I]: 3.235 (120, 102, 1̅02) 100, 2.873 (200) 40, 2.985 (1̅21, 112, 121) 37, 2.774 (022) 30, 3.501 (021, 012) 29, 2.220 (221, 2̅21, 212) 23, 1.990 (222, 2̅22) 21, and 1.715 (320) 22. The crystal structure (R1= 0.052) is based on sheets of corner-sharing uranyl square bipyramids and tellurate octahedra, with Pb atoms between the sheets. Markcooperite is the first compound to show Te6+substitution for U6+within the same crystallographic site. Markcooperite is structurally related to synthetic Pb(UO2)O2.

Ottoite, Pb2TeO5, is a new tellurate from Otto Mountain near Baker, California. Most of the mining on Otto Mountain occurred between 1940 and 1970 and is attributed to Otto Fuetterer, for whom the mountain is now named. The new mineral occurs on fracture surfaces and in small vugs in brecciated quartz veins, which intersect granitic rocks. Ottoite is directly associated with acanthite, bromine-rich chlorargyrite, gold, iodargyrite, khinite, wulfenite, and four other new tellurates: housleyite, markcooperite, thorneite, and timroseite. Various other secondary minerals occur in the veins, including two other new secondary tellurium minerals, paratimroseite and telluroperite. Ottoite and most other secondary minerals of the quartz veins are interpreted as having formed from the partial oxidation of primary sulfides and tellurides during or following brecciation of the veins. A later generation of quartz mineralization then recemented the breccias, effectively isolating and protecting the secondary mineralization from further alteration. Ottoite is monoclinic, space group I2/a, with the unit cell: a = 7.5353(6), b = 5.7142(5), c = 10.8981(12) Å, β = 91.330(6)°, V = 469.13(8) Å3, and Z = 4. The mineral occurs as complex spear-shaped crystals in subparallel to divergent intergrowths. It is yellow and transparent to translucent, with a pale yellow streak and adamantine luster. Mohs hardness is estimated at 3. The mineral is brittle, with an irregular fracture and two cleavages in the [100] zone at ~90°-possibly on {010} and {001}. The calculated density is 8.721 g/cm3. Ottoite is biaxial (-), with a large 2V, but indices of refraction are too high to be measured. The optic orientation could only partially be determined: Y ≈ a. No pleochroism was observed. Electron microprobe analyses provided the following averages: PbO 68.88 and TeO328.03, total 96.95 wt%; the empirical formula (based on O = 5) is Pb1.96Te6+1.01O5. The strongest powder X-ray diffraction lines are [dobsin Å (hkl) I]: 3.131 (2̅02) 64, 3.055 (013) 90, 3.015 (211) 100, 2.112 (2̅22) 29, 1.810 (006, 2̅15) 21, 1.773 (4̅11, 402) 43, 1.686 (033, 231) 20. The crystal structure (R1= 0.020) consists of straight chains of trans-corner-sharing Te6+O6octahedra parallel to a, which are joined by bonds to Pb atoms. The Pb atom exhibit markedly lopsided 11-coordination, typical of Pb2+with stereoactive 6s2lone-pair electrons. The powder X-ray diffraction pattern of ottoite is very similar to that reported for girdite. Examination of girdite type material suggests that its description was based upon data obtained from at least two and possibly three different phases, one of which may correspond to ottoite.

Kapundaite, ideally (Na,Ca)2Fe43+(PO4)4(OH)3∙5H2O, is a new mineral (IMA2009-047) from Toms phosphate quarry, Kapunda, South Australia, Australia. The new mineral occurs as cavernous aggregates of fibers up to several centimeters across, associated with leucophosphite, natrodufrenite, and meurigite-Na crystals and amorphous brown, black, and/or greenish coatings. Individual kapundaite crystals are very thin flattened fibers up to a few millimeters in length, but typically no more than a few micrometers in thickness. The main form observed is {100}; other forms in the [010] zone are present, but cannot be measured. Crystals of kapundaite are pale to golden yellow, transparent to translucent, have a yellow streak and silky luster, and are non-fluorescent. Mohs hardness is estimated to be about 3; no twinning or cleavage was observed. Kapundaite is biaxial (+), with indices of refraction α = 1.717(3), β = 1.737(3), and γ = 1.790(3). 2V could not be measured; 2Vcalcis 64.7°. The optical orientation is Z = b, Y ≈ c with weak pleochroism: X = nearly colorless, Y = light brown, Z = pale brown; absorption: Y > Z > X. No dispersion was observed. The empirical chemical formula (mean of seven electron microprobe analyses) calculated on the basis of 24 O is (Ca1.13Na0.95)Σ2.08(Fe3+3.83Mn0.03Al0.02Mg0.01)Σ3.89P3.92O16(OH)3·5H2.11O. Kapundaite is triclinic, space group P1, a = 6.317(5), b = 7.698(6), c = 9.768(7) Å, α = 105.53(1)°, β = 99.24(2)°, γ = 90.09(2)°, V = 451.2(6) Å3, and Z = 1. The five strongest lines in the powder X-ray diffraction pattern are [dobsin Å (I) (hkl)]: 9.338 (100) (001), 2.753 (64) (21̄1), 5.173 (52) (011), 2.417 (48) (2̄1̄3, 202, 01̄4), and 3.828 (45) (02̄1). The crystal structure was solved from single-crystal X-ray diffraction data using synchrotron radiation and refined to R1= 0.1382 on the basis of 816 unique reflections with Fo > 4σF. The structure of kapundaite is based on a unique corrugated octahedral-tetrahedral sheet, which is composed of two types of chains parallel to a. Kapundaite is structurally related to mélonjosephite. The mineral is named for the nearest town to the quarry.

Joëlbruggerite, ideally Pb3Zn3(Sb5+,Te6+)As2O13(OH,O), is a new arsenate mineral (IMA 2008-034) and the Sb5+analog of dugganite, from the Black Pine mine, 14.5 km northwest of Philipsburg, Granite County, Montana. It is usually found perched on mimetite; other species that may be present include malachite, azurite, pseudomalachite, chalcocite, beudantite-corkite, duftite, dugganite, and kuksite, in milky quartz veins. Joëlbruggerite occurs as barrel-shaped or prismatic crystals up to about 50 μm across in various shades of purple. The crystals have an adamantine luster and a white streak. Mohs hardness is about 3. The fracture is irregular, and the tenacity is brittle. Joëlbruggerite crystals are uniaxial (-), with a calculated refractive index of n = 1.993, and weakly pleochroic: X = Y = gray, Z = purple; absorption: Z > X = Y. Crystals show straight extinction and are length-fast. The empirical chemical formula (mean of 5 electron microprobe analyses) calculated on the basis of 14 [O + OH] anions is Pb3.112(Zn2.689Fe2+0.185)Σ2.874(Sb5+0.650Te6+0.451)Σ1.101(As1.551P0.203Si0.160)Σ1.914O13.335(OH)0.665. Joëlbruggerite is trigonal, space group P321, a = 8.4803(17), c = 5.2334(12) Å, V = 325.94(12) Å3, Z = 1. The five strongest lines in the powder X-ray diffraction pattern are [dobs in Å (I) (hkl)]: 3.298 (100) (111), 3.008 (89) (021), 1.905 (39) (122, 131), 2.456 (36) (012, 121, 030), and 1.609 (30) (112, 132, 231, 140). The crystal structure was solved from single-crystal X-ray diffraction data and refined to R1= 0.038 on the basis of 604 unique reflections with F > 4σ(F). It is composed of heteropolyhedral sheets of edge-sharing (Sb,Te)O6octahedra and PbO8disphenoids, oriented parallel to (001). The sheets are cross-linked by AsO4and ZnO4tetrahedra, which share corners to form an interlinked, two- and threeconnected two-dimensional net parallel to (001). The mineral is named for Joël Brugger (born 1967), Swiss-Australian mineralogist, for his contributions to mineralogy.

Kintoreite, PbFe3H0.94[(PO4)0.97(SO4)0.03]2(OH)6, and zincian kintoreite, PbZn0.3Fe3H0.24[(PO4)0.54(SO4)0.08(AsO4)0.38]2(OH)6, have rhombohedral symmetry, space group R3m, with hexagonal cell parameters a = 7.2963(5) Å, c = 16.8491(5) Å, and a = 7.3789(3) Å, c = 16.8552(7) Å, respectively. The structures have been refined using single-crystal X-ray data to R1= 0.030 for 374 observed reflections and R1= 0.035 for 399 observed reflections, respectively. The structures of both minerals comprise rhombohedral stacking of (001) composite layers of corner-shared octahedra and tetrahedra with Pb atoms occupying icosahedral sites between the layers, as in the alunite-type structure. The cornerconnected octahedra form three-membered and six-membered rings as in hexagonal tungsten bronzes. The structure of zincian kintoreite differs from other alunite-type structures in having partial occupation, by Zn, of new sites within the six-membered rings in the octahedral layers. The Zn is displaced to an off-center position in the hexagonal ring, where it assumes fivefold trigonal-bipyramidal coordination, to three of the hydroxyl anions forming the ring, and to the apical O anions of the XO4tetrahedra on opposite sides of the ring. The different structural modes of Zn incorporation into SO4-dominant and (P,As)O4-dominant members of A2+B33+(XO4)2(OH)6alunite-type minerals are discussed in terms of the different charge-compensation mechanisms involved.

Pericytes have the potential to be developed as a cell therapy for the treatment of wounds; however, the efficacy of any cell therapy relies on the successful delivery of intact and functioning cells. Here, the effect of delivering pericytes on wound repair was assessed alongside the development of a surface-functionalized pericyte patch. Plasma polymerization (PP) was used to functionalize the surface of silicone patches with heptylamine (HA) or acrylic acid (AA) monomers. Human pericytes were subsequently delivered to murine excisional wounds by intradermal injection or using the pericyte-laden patches and the comparative effects on wound healing, inflammation and revascularization determined. The AA surface provided the superior transfer of the cells to de-epidermized dermis. Excisional murine wounds treated either with pericytes injected directly into the wound or with the pericyte-laden AA patches showed improved healing with decreased neutrophil infiltration and reduced numbers of macrophages in the wounds. Pericyte delivery also enhanced angiogenesis through a mechanism independent of VEGF signalling. Pericytes, when delivered to wounds, improved healing responses by dampening inflammation and promoting angiogenesis. Delivery of pericytes using PP-AA-functionalized patches was equally as effective as direct injection of pericytes into wounds. Pericyte-functionalized dressings may therefore be a clinically relevant approach for the treatment of wounds.