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Sulfosalt assemblages in a specimen from the Boliden Au-Cu-(As) deposit in northern Sweden, comprise micrometre to nanometre scale intergrowths of Se-rich izoklakeite and tintinaite with average formulae and calculated homologue number (N) given as: (Cu1.88Fe0.18)2.06(Pb22.92Ag1.47Cd0.01Zn0.01)24.41(Sb13 .12Bi8.69 )21.8(S50.19Se6.43Te0.12)56.73, N = 3.83, and (Cu1.31Fe0.74)2.05(Pb10.58Ag0.18Cd0.05Zn0.02)10.83(Sb10 .2Bi5.23) 15.43(S32.22Se2.46)34.7, N = 2.05, respectively. Tintinaite coexists with (Bi, Se)-rich jamesonite. High-angle annular dark field scanning transmission electron microscopy (HAADF STEM) imaging reveals chessboard structures comprising PbS and SnS modules with the number of atoms in the octahedral (M) sites counted as: n1 = 18 and n2 = 8 for tintinaite and n1 = 30 and n2 = 16 for izoklakeite. The homologue number can be calculated using the formula: N = (n1/6)-1 and N = n2/4 for PbS and SnS modules giving NTti = 2 and NIz = 4. A new N = 3 homologue, defined by n = 12 and n = 24 SnS and PbS modules, respectively, is identified as single or double units within areas with intergrowths between kobellite and izoklakeite. HAADF STEM imaging also reveals features attributable to lone electron pair micelles within the Sb-rich kobellite homologues. Atomic-resolution EDS STEM chemical mapping of Pb-Bi-Sb-sulfosalts shows a correlation with crystal structural modularity. The maps also highlight sites in the SnS modules of tintinaite in which Sb > Bi. Coherent nanoscale intergrowths between tintinaite and izoklakeite define jigsaw patterns evolving from chessboard structures and are considered to have formed during co-crystallisation of the two phases. Displacement textures and crosscutting veinlets (a few nm in width) are interpreted as evidence for superimposed syn-metamorphic deformation and are associated with the redistribution of Bi and Se. Imaging and mapping using HAADF STEM techniques is well suited to characterisation of Pb-Sb-Bi-sulfosalt phases, offering largely untapped potential to unravel the evolution of chessboard structures with applications across mineralogy but also extending into allied fields.

Plumboperloffite, PbMn2+2Fe3+2(PO4)3(OH)3, is a new mineral and member of the bjarebyite group from Wiperaminga Hill West Quarry, Boolcoomatta Reserve, Olary Province, South Australia, Australia. The mineral was found in a single cavity in triplite-barbosalite matrix associated with fluorapatite, phosphosiderite, natrodufrénite and fluorite. The mineral forms intergrowths of subparallel, thin tabular to bladed crystals. Individual crystals are up to 40 µm in length. Plumboperloffite is brownish orange in colour with a vitreous lustre. The mineral has brittle tenacity, an excellent cleavage on {100} and uneven fracture. The calculated density is 4.416 g/cm3. Plumboperloffite is biaxial (+), α = 1.87(1), β = 1.88(1) and γ = 1.89(1) as measured in white light. The measured 2V is 88(1)°. Dispersion is apparently strong, based on extinction colours and the orientation is Y = b. The pleochroism in shades of yellow brown is X < Z < Y. Electron microprobe analysis gave the empirical formula (based on 15 O apfu) (Pb0.92Ca0.04Ba0.01K0.01)Σ0.98(Mn2+1.84Fe2+0.13)Σ 1.97(Fe3+1 .97Al0.03)Σ2.00(P3.01O11.94)(OH)Σ3.06. Plumboperloffite is monoclinic, space group P21/m with a = 9.1765(18), b = 12.340(3), c = 5.0092(10) Å, β = 101.01(3)°, V = 556.8(2) Å3 and Z = 2. The crystal structure has been refined using X-ray single-crystal data to a final R1 = 0.0207 on the basis of 1417 reflections with Fo > 4σ(Fo). The mineral is isostructural with members of the bjarebyite-group minerals.

National levels of personal health-care access and quality can be approximated by measuring mortality rates from causes that should not be fatal in the presence of effective medical care (ie, amenable mortality). Previous analyses of mortality amenable to health care only focused on high-income countries and faced several methodological challenges. In the present analysis, we use the highly standardised cause of death and risk factor estimates generated through the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) to improve and expand the quantification of personal health-care access and quality for 195 countries and territories from 1990 to 2015. We mapped the most widely used list of causes amenable to personal health care developed by Nolte and McKee to 32 GBD causes. We accounted for variations in cause of death certification and misclassifications through the extensive data standardisation processes and redistribution algorithms developed for GBD. To isolate the effects of personal health-care access and quality, we risk-standardised cause-specific mortality rates for each geography-year by removing the joint effects of local environmental and behavioural risks, and adding back the global levels of risk exposure as estimated for GBD 2015. We employed principal component analysis to create a single, interpretable summary measure–the Healthcare Quality and Access (HAQ) Index–on a scale of 0 to 100. The HAQ Index showed strong convergence validity as compared with other health-system indicators, including health expenditure per capita (r=0·88), an index of 11 universal health coverage interventions (r=0·83), and human resources for health per 1000 (r=0·77). We used free disposal hull analysis with bootstrapping to produce a frontier based on the relationship between the HAQ Index and the Socio-demographic Index (SDI), a measure of overall development consisting of income per capita, average years of education, and total fertility rates. This frontier allowed us to better quantify the maximum levels of personal health-care access and quality achieved across the development spectrum, and pinpoint geographies where gaps between observed and potential levels have narrowed or widened over time. Between 1990 and 2015, nearly all countries and territories saw their HAQ Index values improve; nonetheless, the difference between the highest and lowest observed HAQ Index was larger in 2015 than in 1990, ranging from 28·6 to 94·6. Of 195 geographies, 167 had statistically significant increases in HAQ Index levels since 1990, with South Korea, Turkey, Peru, China, and the Maldives recording among the largest gains by 2015. Performance on the HAQ Index and individual causes showed distinct patterns by region and level of development, yet substantial heterogeneities emerged for several causes, including cancers in highest-SDI countries; chronic kidney disease, diabetes, diarrhoeal diseases, and lower respiratory infections among middle-SDI countries; and measles and tetanus among lowest-SDI countries. While the global HAQ Index average rose from 40·7 (95% uncertainty interval, 39·0–42·8) in 1990 to 53·7 (52·2–55·4) in 2015, far less progress occurred in narrowing the gap between observed HAQ Index values and maximum levels achieved; at the global level, the difference between the observed and frontier HAQ Index only decreased from 21·2 in 1990 to 20·1 in 2015. If every country and territory had achieved the highest observed HAQ Index by their corresponding level of SDI, the global average would have been 73·8 in 2015. Several countries, particularly in eastern and western sub-Saharan Africa, reached HAQ Index values similar to or beyond their development levels, whereas others, namely in southern sub-Saharan Africa, the Middle East, and south Asia, lagged behind what geographies of similar development attained between 1990 and 2015. This novel extension of the GBD Study shows the untapped potential for personal health-care access and quality improvement across the development spectrum. Amid substantive advances in personal health care at the national level, heterogeneous patterns for individual causes in given countries or territories suggest that few places have consistently achieved optimal health-care access and quality across health-system functions and therapeutic areas. This is especially evident in middle-SDI countries, many of which have recently undergone or are currently experiencing epidemiological transitions. The HAQ Index, if paired with other measures of health-system characteristics such as intervention coverage, could provide a robust avenue for tracking progress on universal health coverage and identifying local priorities for strengthening personal health-care quality and access throughout the world. Bill & Melinda Gates Foundation.

The Dexing porphyry Cu deposit is the largest Cu deposit in eastern China, with total reserves of 8.4 Mt Cu. The Dexing porphyries have geochemical characteristics typical of adakites: they are similar to examples in the Circum-Pacific Belt and in the Lower Yangtze River Belt but different from adakites from the Dabie Mountains and the Tibetan Plateau. Ce4+/Ce3+ and (Eu/Eu*)N values calculated from zircon trace-element compositions vary from 495 to 1922 and from 0.51 to 0.82, respectively, and reflect high oxygen fugacity similar to that measured in or inferred for porphyry Cu-Au deposits in the South America. The high oxygen fugacity is consistent with abundant anhydrite and magnetite-hematite intergrowths in the porphyry, which indicate that the highest oxygen fugacity of Dexing porphyry reached the hematite-magnetite buffer. Based on the geochemical characteristics and the drifting history of the Pacific Plate, we propose that the Dexing adakitic porphyries formed through slab melting, most likely during subduction of an aseismic ridge in the Pacific Plate in the Mid-Jurassic.

A meta-porphyritic granitoid in the Makrohar Granulite Belt, Central India contains extensive myrmekite. This work evaluates the controls of fluid in relation to deformation and the formation of myrmekite all along the periphery of an alkali-feldspar megacryst. Two different myrmekite morphologies are present: (1) vermicular intergrowth of plagioclase (An38-39) and quartz (Myr1); and (2) polygonal aggregates of coarse plagioclase (An45-46) and quartz (Myr2). Petrographic features suggest that myrmekite Myr1 nucleates on alkali-feldspar and plagioclase porphyroclasts and the myrmekite front moved into the alkali feldspar by replacing it; and that myrmekite Myr2 and the secondary biotite which replaces plagioclase porphyroclasts and garnet form together. Deformation had a decisive role in forming the polygonal aggregates of Myr2, however field and microtextural features do not support any significant control of deformation during the formation of Myr1. Reaction modelling and a mass-balance calculation suggest that Ca and Na are added to, and K is removed from, the alkali feldspar during the myrmekite formation at nearly constant Si and Al. However, the secondary biotite-forming reaction, consumes K and releases Ca. Interpretation of the reaction textures in different isothermal-isobaric sections of µK2O-µCaO in the KCFASH system suggest that CaO and K2O moved in opposite directions for myrmekitisation and along their respective chemical potential gradients created between the sites of formation of myrmekite and secondary biotite. The feedback mechanism which operated between the two reaction sites was controlled by infiltration of brine-rich fluid in the meta-granitoid during a regional hydration event (550-600°C and 5-6 kbar). Volume reduction of ∼10% during the formation Myr1 and Myr2 drew the brine-rich fluid towards the alkali feldspar and thus facilitated the process of myrmekite formation. Variation in the morphology of quartz in the myrmekite is attributed to the cooling of the complex.

Kvacekite is a new mineral species discovered in a sample collected from the now abandoned Bukov uranium mine, western Moravia, Czech Republic. It occurs as rare anhedral grains, up to 15 µm in size, associated with nickeltyrrellite, tyrrellite, berzelianite, hakite-(Zn), hakite-(Cd), eucairite, clausthalite, and gold in calcite gangue. In reflected light, kvacekite is white with a faint yellowish shade; bireflectance, pleochroism and anisotropy are absent. Internal reflections were not observed. Reflectance values for the four COM wavelengths for kvacekite in air [R (%) (λ in nm)] are: 54.9 (470); 53.5 (546); 52.6 (589); and 52.2 (650). The empirical formula, based on electron-microprobe analyses (EPMA), is (Ni0.95Cu0.04Co0.03)Σ1.02Sb1.00(Se0.97S0.01)Σ0.98. The ideal formula is NiSbSe, which requires (in wt.%) Ni 22.63, Sb 46.93, Se 30.44, total 100.00. Kvacekite is cubic, P213, with unit-cell parameters a = 6.09013(13) Å, V = 225.881(15) Å3 and Z = 4. The strongest reflections in the X-ray powder diffraction pattern of synthetic kvacekite [d, Å (I) hkl] are: 3.0458 (11) 200; 2.7242 (100) 201, 210; 2.4867 (71) 211; 1.8632(39) 311; 1.6277(29) 321, 312; and 1.3290 (13) 421. Given the similarity with ullmannite, NiSbS, the crystal structure was refined from the powder X-ray diffraction data starting from those atomic coordinates using the synthetic analogue of kvacekite. Its crystal structure is formed by corner-sharing [NiSb3Se3] octahedra which form a three-dimensional network. The identity of the natural kvacekite and synthetic cubic NiSbSe were confirmed by a study of their chemical composition, reflectance measurements, Raman spectroscopy and electron back-scattered diffraction (EBSD) measurements on the mineral. Kvacekite is named after Milan Kvacek (1930-1993), a prominent Czech mineralogist. The mineral and its name have been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA2023-095).

Cotype material of stibiogoldfieldite from the Mohawk mine, Goldfield, Nevada, USA, has been examined in order to collect single-crystal X-ray diffraction data of Te-rich stibiogoldfieldite and to characterise the associated Ag-Bi-(S,Se) phase. Tellurium-rich stibiogoldfieldite, with empirical formula (Cu11.30Ag0.03)Σ11.33(Sb0.80As0.57Bi0.06Te2.57)Σ4.00 (S12.8 3Se0.20)Σ13.03, is cubic, space group I$\\bar{4}$3m, with unit-cell parameters a = 10.2947(3) Å and V = 1091.04(10) Å3. Its crystal structure has been refined to R1 = 0.0161 for 397 unique reflections with Fo > 4σ(Fo) and 25 refined parameters. The structure refinement confirmed the occurrence of a vacancy at the M(2) site, in agreement with the substitution M(2)Cu+ + X(3)(Sb/As)3+ = M(2)∎ + X(3)Te4+. The Ag-Bi-(S,Se) phase was identified as the 6P homologue of the pavonite series, namely dantopaite. Its empirical formula is Cu1.36Ag4.39Pb0.12Bi12.62Sb0.06(S14.01Se7.91Te0.08), showing an exceptionally high Se content. Unit-cell parameters of Se-bearing dantopaite are a = 13.518(2), b = 4.0898(6), c = 18.984(3) Å, β = 106.816(6)°, V = 1004.7(3) Å3 and space group C2/m. The crystal structure was refined to R1 = 0.0504 for 1230 unique reflections with Fo > 4σ(Fo) and 82 refined parameters. The metal excess (∼0.55 atoms per formula unit) of this pavonite homologue is mainly due to the accumulation of Ag and Cu in the thin slab of the crystal structure, whereas the high Se content is related to the partial replacement of S occurring preferentially in the thick PbS-like slab. Domains richer in Se and Pb in dantopaite, with empirical formula Cu0.89Ag4.50Pb0.49Bi12.53Sb0.07(S11.26Se10.74), were also identified, as grains up to 30 µm in size intimately intergrown with bohdanowiczite, indicating the possibility of a wide Se-to-S substitution in dantopaite.

The new mineral libbyite (IMA2022-091), (NH4)2(Na2∎)[(UO2)2(SO4)3(H2O)]2·7H2O, was found in the Blue Lizard mine, San Juan County, Utah, USA, where it occurs as tightly intergrown aggregates of light green-yellow equant crystals in a secondary assemblage with bobcookite, coquimbite, halotrichite, metavoltine, rhomboclase, römerite, tamarugite, voltaite and zincorietveldite. The streak is very pale green yellow and the fluorescence is strong green under 405 nm ultraviolet light. Crystals are transparent with vitreous lustre. The tenacity is brittle, the Mohs hardness is ∼2 1/2, the fracture is curved. The mineral is soluble in H2O and has a calculated density of 3.465 g·cm-3. The mineral is optically uniaxial (-) with ω = 1.581(2) and (open e) = 1.540(2). Electron microprobe analyses provided (NH4)1.92K0.08Na2.00U4.00S6.00O41H18.00. Libbyite is tetragonal, P41212, a = 10.7037(11), c = 31.824(2) Å, V = 3646.0(8) Å3 and Z = 4. The structural unit is a uranyl-sulfate sheet that has the same topology as the sheets in several synthetic uranyl selenates.

Rundqvistite-(Ce), ideally Na3(Sr3Ce)(Zn2Si8O24), is a new mineral from the Darai-Pioz alkaline massif, Tien Shan Mountains, Tajikistan. The mineral occurs as elongated grains up to 0.1 mm long and up to 0.03 mm thick embedded in quartz-pectolite aggregate in a silexite-like peralkaline pegmatite. Associated minerals are quartz, fluorite, pectolite, baratovite, aegirine, leucosphenite, neptunite, reedmergnerite, orlovite, sokolovaite, mendeleevite-(Ce), odigitriaite, pekovite, zeravshanite, kirchhoffite and garmite. The mineral is colourless with a vitreous lustre and a white streak, brittle, Dmeas. is 3.70(2) and Dcalc. is 3.709 g/cm3. Rundqvistite-(Ce) is monoclinic, space group P21/c, a = 5.1934(16), b = 7.8934(16), c = 26.011(5) Å, β = 90.02(3)° and V = 1066.3(4) Å3. The chemical composition of rundqvistite-(Ce) is SiO2 40.17, La2O3 2.64, Ce2O3 7.55, Pr2O3 0.80, Nd2O3 2.43, Sm2O3 0.33, Eu2O3 0.09, Gd2O3 0.24, Tb2O3 0.18, Dy2O3 0.21, PbO 1.03, SrO 19.83, FeO 0.37, ZnO 13.08, CaO 2.55, Na2O 8.04, total 99.54 wt.%. The empirical formula calculated on 24 O apfu (atoms per formula unit) is Na3.10Sr2.29Ca0.54Pb0.06(Ce0.55La0.19Nd0.17Pr0.06Sm0.02Gd0.02 Eu0.01Tb0.01Dy0.01)Σ1.04Zn1.92Fe0.06Si8.00O24, Z = 2. The structural formula based on refined site-occupancies is (Na2.94Sr0.06)Σ3.00 [(Sr2.23Ca0.54Pb0.06Na0.13)Σ2.96Ln3+1.04]Σ4.00[(Zn1.92Fe2 +0.06)Σ1.98Si8O24], where Ln3+1.04 = (Ce0.55La0.19Nd0.17Pr0.06Sm0.02Gd0.02Eu0.01Tb0.01Dy0.01)Σ1.0 4. The crystal structure of rundqvistite-(Ce) was refined to R1 = 2.76% on the basis of 3184 unique reflections [F > 4σ|F|]. In rundqvistite-(Ce), the main structural unit is a (Zn2Si8O24)12- sheet parallel to (100). In the sheet, the Si and Zn tetrahedra form four-, five- and eight-membered rings. The interstitial cations at the Na and M(1-3) sites sum to [Na3(Sr3Ce)]12- apfu. The Na and M(1-3) polyhedra share common edges to form a layer. Rundqvistite-(Ce) is a structural analogue of vladykinite, ideally Na3Sr4(Fe2+Fe3+)Si8O24. Rundqvistite-(Ce) and vladykinite are related by the following substitution: [8]Ce3+ + [4](Zn2+)2 ⇌ [8]Sr2+ + [4](Fe2+Fe3+). The mineral is named after Dmitry Vasilievich Rundqvist (1930-2022), a prominent Russian geologist and an expert on the geology of ore deposits, metallogeny and mineralogy of Precambrian rocks.

Mangani-eckermannite, ideally NaNa2(Mg4Mn3+)Si8O22(OH)2, is a new member of the amphibole supergroup found at Tanohata Mine, Shimohei District, Iwate Prefecture, Japan. It occurs as prismatic crystals up to 0.3 × 0.2 mm and their aggregates up to 1 mm intergrown with braunite, vittinkiite and quartz. Mangani-eckermannite is cherry-red to very dark red and reddish-brown in thicker grains. It is translucent with a pinkish white streak and vitreous lustre. It is brittle, fracture is stepped along crystal elongation and uneven across a crystal. Cleavage is perfect on {110}. Mohs hardness is 6. Dmeas = 3.16(2) and Dcalc = 3.186 g/cm3. The mineral is optically biaxial (-), with α = 1.645(3), β = 1.668(2), γ = 1.675(3) (589 nm); 2Vmeas = 60(10)°, 2Vcalc = 57°. The empirical formula derived from electron microprobe analysis, secondary-ion mass spectrometry and single-crystal structure refinement and calculated on the basis of 24 (O+OH) atoms per formula unit (apfu) is A(Na0.74K0.24∎0.02)Σ1.00B(Na1.52Ca0.24Mn2+0.24)Σ2.00C(M g2.54Mn2+1.45Mn3+0.71Fe3+0.26Ti0.04)Σ5.00T(Si7.97Al0.03)Σ8. 00O22W[(OH)1.52O0.48]Σ2.00. Mangani-eckermannite is monoclinic, space group C2/m, a = 9.9533(4), b = 18.1440(7), c = 5.2970(2) Å, β = 103.948(4)°, V = 928.39(6) Å3 and Z = 2. The strongest lines of the powder X-ray diffraction pattern [d, Å (I, %)(hkl)] are: 8.52(100)(110); 4.54(25)(040); 3.41(29)(131); 3.16(23)(310,201); 2.721(37)(151); 2.533(26)(2̄02). The crystal structure was refined to R1 = 0.0264 for 1001 independent reflections with I > 2σ(I). The place of mangani-eckermannite in the nomenclature of the amphibole supergroup is discussed and the status of mangano-ferri-eckermannite as a valid mineral species and successor of 'kôzulite' is questioned.