Laueite/stewartite epitaxy was studied using single-crystal diffraction applied to a composite crystal from Hagendorf-Süd, Bavaria. The orientation relationships between the crystals of the two minerals was facilitated by using a non-conventional B$\bar {1}$ space group setting for stewartite, giving unit cells with parallel axes and with as = 2al, bs = bl and cs = 2cl. Face indexing of the crystals of the two minerals confirmed the epitaxial relationship, with the {100} and {010} faces parallel. The plane of epitaxy is {010}. Refinement of laueite and stewartite datasets extracted from the composite-crystal data collection showed a significant decrease in the mean Mn-site bond distances in laueite, consistent with chemical analyses of the crystals that gave site compositions of Mn0.92Fe3+0.08 for stewartite and Mn0.66Mg0.17Fe3+0.17 for laueite. The epitaxial growth of laueite on {010} planes of stewartite appears to have been initiated by a change in solution chemistry. Possible paragenesis of the secondary phosphate minerals from primary triphylite is discussed.

On the upper reaches of the Tigris and Euphrates, archaeologists encounter evidence that challenges conventional understandings of early state formation as a transition from ‘small-scale, egalitarian’ to ‘large-scale, stratified’ societies. One such location is the Early Bronze Age cemetery of Başur Höyük, which presents evidence of grand funerary rituals—including ‘retainer burials’ and spectacular deposits of metallic wealth—in an otherwise small-scale, egalitarian setting. A further, puzzling feature of this cemetery is the preponderance of teenagers in the richest tombs. Here we describe the combined results of archaeological and anthropological analysis at Başur Höyük, including ancient DNA, and consider the challenges they pose to traditional accounts of early state formation.

We present a new model for understanding ice cliff dynamics within a debris-covered glacier ablation zone. This simple energy-balance model incorporates a moving frame of reference, made necessary by the melt of the surrounding debris-covered ice. In so doing, this also formalises how different types of field measurements can be utilised and compared. Our predictions include showing: ice cliffs can endogenously select their own slope angles; that there should be an indifference between illuminated north- and south-facing ice cliff slopes; that ice cliffs grow steeper with thicker debris layers; that ice cliffs cannot stably exist below a certain critical debris thickness and that some modelling of ice cliffs (when not incorporating the moving frame) may incorrectly estimate ice mass losses. All of our results are produced using parametrisations from Baltoro Glacier, Karakoram.

Sperlingite, (H2O)K(Mn2+Fe3+)(Al2Ti)(PO4)4[O(OH)][(H2O)9(OH)]⋅4H2O, is a new monoclinic member of the paulkerrite group, from the Hagendorf-Süd pegmatite, Oberpfalz, Bavaria, Germany. It was found in corrosion pits of altered zwieselite, in association with columbite, hopeite, leucophosphite, mitridatite, scholzite, orange–brown zincoberaunite sprays and tiny green crystals of zincolibethenite. Sperlingite forms colourless prisms with pyramidal terminations, which are predominantly only 5 to 20 μm in size, rarely to 60 μm and frequently are multiply intergrown and are overgrown with smaller crystals. The crystals are flattened on {010} and slightly elongated along [100] with forms {010}, {001} and {111}. Twinning occurs by rotation about c. The calculated density is 2.40 g⋅cm–3. Optically, sperlingite crystals are biaxial (+), α = 1.600(est), β = 1.615(5), γ = 1.635(5) (white light) and 2V (calc.) = 82.7°. The optical orientation is X = b, Y = c and Z = a. Neither dispersion nor pleochroism were observed. The empirical formula from electron microprobe analyses and structure refinement is A1[(H2O)0.96K0.04]Σ1.00 A2(K0.52□0.48)Σ1.00 M1(Mn2+0.60Mg0.33Zn0.29Fe3+0.77)Σ1.99 M2+M3(Al1.05Ti4+1.33Fe3+0.62)Σ3.00(PO4)4 X[F0.19(OH)0.94O0.87]Σ2.00[(H2O)9.23(OH)0.77]Σ10.00⋅3.96H2O. Sperlingite has monoclinic symmetry with space group P21/c and unit-cell parameters a = 10.428(2) Å, b = 20.281(4) Å, c = 12.223(2) Å, β = 90.10(3)°, V = 2585.0(8) Å3 and Z = 4. The crystal structure was refined using synchrotron single-crystal data to wRobs = 0.058 for 5608 reflections with I > 3σ(I). Sperlingite is the first paulkerrite-group mineral to have co-dominant divalent and trivalent cations at the M1 sites; All other reported members have Mn2+ or Mg dominant at M1. Local charge balance for Fe3+ at M1 is achieved by H2O → OH– at H2O coordinated to M1.

Hydroxylbenyacarite, (H2O)2Mn2(Ti2Fe)(PO4)4[O(OH)](H2O)10⋅4H2O, is a new paulkerrite-group mineral from the El Criollo mine, Cordoba Province, Argentina (IMA2023–079). It was found in specimens of altered triplite, in association with bermanite, phosphosiderite, quartz, strengite and manganese oxides.

Hydroxylbenyacarite occurs as light greenish-yellow rhombic tablets with dimensions of typically 20 to 50 μm, occasionally to 400 μm. The crystals are flattened on {010}, slightly elongated on [001] and bounded by the {111} and {010} forms. The calculated density is 2.32 g cm–3. Optically, hydroxylbenyacarite crystals are biaxial (+), with α = 1.608(3), β = 1.624(3), γ = 1.642(3) (measured in white light) and 2V(meas.) = 88(2)°. The calculated 2V is 87.5°. The empirical formula is Ca0.06 A[K0.46(H2O)0.88□0.66]Σ2.00 M1(Mn1.52Mg0.02Fe2+0.35□0.11)Σ2.00 M2+M3(Fe3+1.21Al0.02Ti1.77)Σ3.00(PO4)4 X[F0.16(OH)0.70O1.14]Σ2.00(H2O)10⋅3.77H2O.

The average crystal structure for hydroxylbenyacarite has space group Pbca and unit cell parameters a = 10.5500(3) Å, b =20.7248(5) Å, c = 12.5023(3) Å, V = 2733.58(12) Å3 and Z = 4. It was refined using single-crystal data to wRobs = 0.074 for 2611 reflections with I > 3σ(I). The crystal structure contains corner-connected linear trimers of Ti-centred octahedra that share corners with PO4 tetrahedra to form 10-member rings parallel to (010). K+ cations and water molecules are located in interstitial sites within the rings. Additional corner-sharing of the PO4 tetrahedra with MnO2(H2O)4 octahedra occurs along [010] to complete the 3D framework structure. A new eight-coordinated interstitial site, previously unreported for paulkerrite-group minerals, is occupied by Ca2+ cations. Weak diffuse diffraction spots in reconstructed precession images for hydroxylbenyacarite violate the a and b glide plane extinctions for Pbca and are consistent with local, unit-cell-scale regions of monoclinic, P21/c structure, in which ordering of the interstitial K+ and Ca2+ cations occurs.

The military invasion of Ukraine has destroyed and damaged extensive built cultural heritage, including churches, museums and monuments. Based on site visits conducted since the invasion, we outline damage to the eleventh-century sites of Boldyni Hory, Chernihiv, and the church, citadel and graveyard at Oster, Chernihiv Oblast.

We demonstrate a fast adjoint-based method to optimise tokamak and stellarator equilibria against a pressure-driven instability known as the infinite-$n$ ideal ballooning mode. We present three finite-$\beta$ (the ratio of thermal to magnetic pressure) equilibria: one tokamak equilibrium and two stellarator equilibria that are unstable against the ballooning mode. Using the self-adjoint property of ideal magnetohydrodynamics, we construct a technique to rapidly calculate the change in the eigenvalue, a measure of ideal ballooning instability. Using the SIMSOPT optimisation framework, we then implement our fast adjoint gradient-based optimiser to minimise the eigenvalue and find stable equilibria for each of the three originally unstable equilibria.

The advent of new non-invasive (largely EEG and MRI-based) methods for recording the activity of critical brain circuits (frontotemporal and subcortical) and networks (Default Mode, Salience, Central Executive), cross-sectionally and longitudinally, as well as concurrently (EEG and fMRI), has led to a focus on whether such techniques could be used to guide individual treatment selection. While this work has commenced with specific relevance to depression and other mood disorders (Goldstein-Piekarski et al., 2022; Hack et al., 2023; Scangos et al., 2023), there is still much to be learnt and a great need to replicate findings across different cohorts and different research centres.

White marble sculpture is a cornerstone of Western art history. Archaeological inquiry, however, has demonstrated that Classical sculpture and its associated architecture were once coloured. The authors examine the Parthenon Sculptures at the British Museum to identify traces of colour and carving on their surfaces. Using close examination and archaeometric techniques, the study shows that the sculptors finished surfaces with textures that reflected specific elements (e.g. skin, wool, linen) and these were then enhanced through the application of colour, including a purple colourant and Egyptian blue. The latter was used extensively to paint elaborate figurative designs on the carved textiles. Despite the complexity of the carved drapery, elaborate ornament was applied to the finish. The findings encourage a reconsideration of the appearance of the Parthenon in the fifth century BC.

Rewitzerite, K(H2O)Mn2(Al2Ti)(PO4)4[O(OH)](H2O)10⋅4H2O, is a new monoclinic member of the paulkerrite group, from the Hagendorf-Süd pegmatite, Oberpfalz, Bavaria, Germany. It was found in specimens of altered zwieselite, in association with rockbridgeite. Rewitzerite forms clusters of colourless elongated hexagonal-shaped prisms, up to 0.1 mm long. The crystals are flattened on {010} and elongated along [100], with forms {010}, {001}, {111} and {$\bar{1}$11}. The calculated density is 2.33 g⋅cm–3. Optically, rewitzerite crystals are biaxial (+), with α = 1.585(2), β = 1.586(2), γ = 1.615(2) (measured in white light) and 2V(meas) = 25(2)°. The empirical formula from electron microprobe analyses and structure refinement is A1[K0.77(H2O)0.23]A2[H2O] M1(Mn2+0.82Mg0.64Fe3+0.43□0.11)Σ2.00 M2+M3(Al1.51Ti4+1.06Fe3+0.43)Σ3.00(PO4)4 X[(OH)0.54F0.42O1.04]Σ2.00(H2O)10⋅4H2O, where □ = vacancy.

Rewitzerite has monoclinic symmetry with space group P21/c and unit-cell parameters a = 10.444(2) Å, b = 20.445(2) Å, c = 12.2690(10)Å, β = 90.17(3)°, V = 2619.8(6) Å3 and Z = 4. The crystal structure was refined using synchrotron single-crystal data to wRobs = 0.068 for 5894 reflections with I > 3σ(I). The crystal structure has the same topology as that for orthorhombic paulkerrite-group minerals but differs primarily in having an ordering of K+ and H2O molecules in different A sites, whereas they are disordered at a single A site in the orthorhombic members of the group.

Protection of Antarctica's biodiversity and ecosystem values is enshrined in the Protocol on Environmental Protection to the Antarctic Treaty, which provides for the designation of Antarctic Specially Protected Areas (ASPAs) to areas with outstanding values. Concern has been raised that existing ASPAs fail to prioritize areas to maximize the likelihood of ensuring the long-term conservation of Antarctic ecosystems and biodiversity. The absence of systematic and representative protection is particularly acute for inland aquatic ecosystems, which support a disproportionate amount of inland biodiversity. This paper promotes the case for overt inclusion of inland waters as a critical component of a representative protected area framework for Antarctica, thereby addressing their current underrepresentation. We set out a structured approach to enable the selection of representative freshwater systems for inclusion in the ASPA framework that, with modification, could also be applied across other Antarctic habitats. We acknowledge an overall lack of information on the biogeography of inland aquatic diversity and recommend increased use of remote data collection along with classification tools to mitigate this, as well as the need for the consideration of catchment-scale processes. Changes that accompany contemporary and anticipated climate change make the need for the conservation of representative biodiversity increasingly urgent.