• Mastodon and on and on…a moving story

      Allington-Jones, L (NatSCA, 2018-02-01)
      This is the latest chapter in the history of the mastodon (Mammut americanum (Kerr, 1792)) specimen on display at the Natural History Museum (NHM) in London (UK), and continues from the story told by Lindsay (1991). The specimen was selected to be one of the new exhibits for the Wonder Bays of the refurbished Hintze Hall, at the heart of the Waterhouse building. Residing, until recently, on open display in a different exhibition space, the mastodon required stabilisation and careful dismantling before transportation and reassembly in its new site.
    • The crystal structure of cesbronite, Cu 3 TeO 4 (OH) 4 : a novel sheet tellurate topology

      Missen, OP; Mills, SJ; Welch, MD; Spratt, J; Rumsey, MS; Birch, WD; Brugger, J (International Union of Crystallography, 2018-01-09)
      The crystal structure of cesbronite has been determined using single-crystal X-ray diffraction and supported by electron-microprobe analysis, powder diffraction and Raman spectroscopy. Cesbronite is orthorhombic, space group Cmcm, with a = 2.93172 (16), b = 11.8414 (6), c = 8.6047 (4) Å and V = 298.72 (3) Å3. The chemical formula of cesbronite has been revised to CuII3TeVIO4(OH)4 from CuII5(TeIVO3)2(OH)6·2H2O. This change has been accepted by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association, Proposal 17-C. The previously reported oxidation state of tellurium has been shown to be incorrect; the crystal structure, bond valence studies and charge balance clearly show tellurium to be hexavalent. The crystal structure of cesbronite is formed from corrugated sheets of edge-sharing CuO6 and (Cu0.5Te0.5)O6 octahedra. The structure determined here is an average structure that has underlying ordering of Cu and Te at one of the two metal sites, designated as M, which has an occupancy Cu0.5Te0.5. This averaging probably arises from an absence of correlation between adjacent polyhedral sheets, as there are two different hydrogen-bonding configurations linking sheets that are related by a ½a offset. Randomised stacking of these two configurations results in the superposition of Cu and Te and leads to the Cu0.5Te0.5 occupancy of the M site in the average structure. Bond-valence analysis is used to choose the most probable Cu/Te ordering scheme and also to identify protonation sites (OH). The chosen ordering scheme and its associated OH sites are shown to be consistent with the revised chemical formula.
    • Impact vaporization and Condensation: Laser Irradiation Experiments with Natural Planetary Materials

      Hamann, C; Hecht, L; Schäffer, S; Heunoske, D; Salge, T; Garbout, A; Osterholz, J; Greshake, A (The Woodlands, Texas, USA, 2018)
    • Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

      Georgieva, MN; Little, CTS; Watson, JS; Sephton, MA; Ball, AD; Glover, AG (2017-12-28)
    • Siidraite, Pb 2 Cu(OH) 2 I 3 , from Broken Hill, New South Wales, Australia: the third halocuprate(I) mineral

      Rumsey, MS; Welch, MD; Kleppe, AK; Spratt, J (E. Schweizerbart’sche Verlagsbuchhandlung, 2017-12-01)
      Siidraite, Pb2Cu(OH)2I3, is a new mineral from the Broken Hill deposit in New South Wales, Australia. It occurs as an extremely rare secondary phase alongside marshite, other lead and copper secondaries and supergene cuprite on a single specimen, BM 84642 preserved in the collection of the Natural History Museum, London. Siidraite is yellow and occurs in crystalline grainy aggregates up to 0.3 mm around relict galena. The mineral is translucent with a vitreous lustre and yellow streak, no cleavages or forms have yet been observed. It is non-fluorescent in mixed-wavelength UV light. The calculated density is 6.505 g cm−3. Siidraite is orthorhombic, space group Fddd, a = 16.7082(9) Å, b = 20.846(1) Å, c = 21.016(1) Å, V = 7320.0(8) Å3 and Z = 32. The empirical formula derived from a combination of electron-microprobe analysis and structure determination is Pb2.06Cu0.89(OH)2I2.97, the ideal formula has (in wt%) 8.01 Cu2O, 50.01 PbO, 42.65 I and 2.02 H2O. The five strongest lines in the calculated X-ray powder diffraction pattern are [(h k l), d obs (Å), I/I max (%)]: [(2 4 6), 2.746, 100], [(4 0 4), 3.270, 81], [(2 6 4), 2.738, 77], [(3 1 5), 3.312, 76], [(3 5 1), 3.296, 69]. The crystal used for structure determination had minor pseudomerohedral twinning on [ 0   1 ‾   1 ] and the structure was refined taking this into account to R 1 = 0.037, wR 2 = 0.052, GooF = 1.016, based upon 1368 unique reflections having I > 2σ(I). The structure of siidraite is a framework comprising an alternation of two structural elements, a cubane-like [Pb4(OH)4]4+ group and a [Cu2I6]4− dimer of edge-sharing CuI4 tetrahedra with non-equivalent Cu. Six halocuprate groups surround each [Pb4(OH)4]4+ nucleus, and each halocuprate group is shared between six adjacent [Pb4(OH)4]4+ groups, five long Pb–I bonds are required to complete the co-ordination of each Pb atom. The resulting Pb(OH)3I5 polyhedra are centred on a tetrahedron of O atoms to form a Pb4(OH)4I16 cluster. Siidraite has a unique composition and structure. It is the third naturally occurring halocuprate(I) after marshite and nantokite. A compositionally similar synthetic compound Pb2Cu2(OH)2I2Br has been described that has cubane and CuI4 groups, but a very different structural topology from that of siidraite. Bideauxite, Pb2Ag(OH)FCl3, which has the [Pb4(OH)4]4+ group, shares some topological features with siidraite.
    • Cleaning Minerals: practical and ethical considerations

      Allington-Jones, L (Geological Curators' Group, 2017-11-01)
      Mineral specimens have a dual nature, both as a scientific resource and an aesthetic pleasure. Combine this with a long history of sampling for study, and the developed nature of most specimens on the commercial market, and it is difficult to relate to the ethical principles of conservation when cleaning minerals.
    • Giant Sequoia: an extraordinary case study involving Carbopol® gel

      McKibbin, C; Allington-Jones, L; Verveniotou, E (Archetype Publishing LtdLondon, 2017-10-18)
      In 2016 a project was undertaken to stabilise and aestheticise the transverse section of giant sequoia on display at the Natural History Museum (NHM) in London, UK. This iconic specimen, which now dominates the top floor of the central hall, was 1300 years old when felled and has been part of the exhibitions for 122 years. Measuring over 4.5 metres in diameter, it posed many challenges during remedial conservation. The largest involved removal of the discoloured waxy substance and opacified shellac-based varnish that had been applied in the early 1980s. Solvent tests revealed that the coating was soluble in Industrial Methylated Spirits (IMS) and that the gel worked most effectively at a 1 hour application time. At longer durations the varnish itself gelled and the waxy component was re-deposited. The waxy substance was effectively removed by wiping with alternate white spirit and IMS swabs.
    • A new metriorhynchid crocodylomorph from the Oxford Clay Formation (Middle Jurassic) of England, with implications for the origin and diversification of Geosaurini

      Foffa, Davide; Young, Mark T; Brusatte, Stephen L; Graham, M; Steel, Lorna (Taylor and Francis, 2017-10-02)
      Metriorhynchids are an extinct group of Jurassic–Cretaceous crocodylomorphs secondarily adapted to a marine lifestyle. A new metriorhynchid crocodylomorph from the Oxford Clay Formation (Callovian, Middle Jurassic) of England is described. The specimen is a large, fragmentary skull and associated single ramus of a lower jaw uniquely preserved in a septarian concretion. The description of the specimen reveals a series of autapomorphies (apicobasal flutings on the middle labial surface of the tooth crowns, greatly enlarged basoccipital tuberosities) and a unique combination of characters that warrant the creation of a new genus and species: Ieldraan melkshamensis gen. et sp. nov. This taxon shares numerous characters with the Late Jurassic–Early Cretaceous genus Geosaurus: tooth crowns that have three apicobasal facets on their labial surface, subtly ornamented skull and lower jaws elements, and reception pits along the lateral margin of the dentary (maxillary overbite). Phylogenetic analysis places this new species as the sister taxon to Geosaurus. The new taxon adds valuable information on the time of origin of the macrophagous subclade Geosaurini, which was initially thought to have evolved and radiated during the Late Jurassic. The presence of Ieldraan melkshamensis, the phylogenetic re-evaluation of Suchodus durobrivensis as a Plesiosuchus sister taxon and recently identified Callovian Dakosaurus-like specimens in the Oxford Clay Formation, indicate that all major Geosaurini lineages originated earlier than previously supposed. This has major implications for the evolution of macropredation in the group. Specifically, we can now demonstrate that the four different forms of true ziphodonty observed in derived geosaurins independently evolved from a single non-functional microziphodont common ancestor.
    • Graham MR. (2017) The remedial conservation and support jacketing of the neotype specimen of the dinosaur Massospondylus carinatus

      Graham, M (PeerJ Inc., 2017-08-09)
      In March 2017 the neotype specimen of the Early Jurassic South African prosauropod dinosaur Massospondylus carinatus was appraised and condition reported at the Evolutionary Studies Institute, University of the Witwatersrand (WITS), Johannesburg, in readiness for remedial conservation and re-storage. The work was necessitated by deterioration of the specimen, which was caused by handling over a number of years and an inadequate and failing support mount. Formally numbered BP/1/4934, but more affectionately known to staff as ‘Big Momma’, the specimen was contained within several individual blocks on flimsy support bases and presented various conservation challenges.These included treatment of fractures and cracking across several surfaces of the fossil and the production of clam shell supports to allow for articulated display within the constraints of an existing display cabinet. Part of the brief was to facilitate safer handling and access for researchers. This project was led by the author who also trained the curatorial and preparation staff at WITS in the methods and techniques employed. The visit was funded by the Palaeontological Scientific Trust (PAST), the DST/NRF Centre of Excellence in Palaeosciences and The University of the Witwatersrand (WITS).
    • The remedial conservation and support jacketing of the neotype specimen of the dinosaur Massospondylus carinatus

      Graham, M (PeerJ, 2017-08-09)
      The remedial conservation and support jacketing of the neotype specimen of the dinosaur Massospondylus carinatus
    • Curious bivalves: Systematic utility and unusual properties of anomalodesmatan mitochondrial genomes

      Williams, ST; Foster, PG; Hughes, C; Harper, EM; Taylor, JD; Littlewood, T; Dyal, P; Hopkins, KP; Briscoe, AG (2017-05)
    • Hydroxyferroroméite, a new secondary weathering mineral from Oms, France

      Mills, S; Christy, A; Rumsey, M; Spratt, J; Bittarello, E; Favreau, G; Ciriotti, M; Berbain, C (2017-04-28)
      Hydroxyferroroméite, ideally (Fe2+ 1.5[]0.5)Sb5+ 2O6(OH), is a new secondary mineral from the Correc d'en Llinassos, Oms, Pyrénées-Orientales Department, France. Hydroxyferroroméite occurs as yellow to yellow-brown powdery boxwork replacements up to about 50μm across after tetrahedrite in a siderite–quartz matrix. No distinct crystals have been observed. The empirical formula (based on 7 (O + OH) per formula unit, pfu) is (Fe2+ 1.07Cu2+ 0.50Zn0.03Sr0.03Ca 0.01[]0.36)Σ2 (Sb5+ 1.88Si0.09Al0.02As0.01)Σ2 O6 ((OH)0.86 O0.14). X-ray photoelectron spectroscopy was used to determine the valence states of Sb, Fe and Cu. Hydroxyferroroméite crystallises in the space group Fd3 m with the pyrochlore structure and hence is a new Fe2+ -dominant member of the roméite group of the pyrochlore supergroup. It has the unit-cell parameters: a = 10.25(3) Å, V = 1077(6) Å3 and Z = 8. A model, based on bond-valence theory, for incorporation of the small Fe2+ cation into a displaced variant of the A site of the pyrochlore structure is proposed.
    • The Airless Project

      Allington-Jones, L; Trafford, A (Natural Sciences Collections Association, 2017-04-20)
      A project to combat pyrite oxidation at the NHM (London, UK) is currently in its second year. The project aims to undertake conservation treatments and store highest risk specimens in low oxygen microenvironments. An emergent benefit of the conservation-driven project has been the digitisation of specimens on the collection management system KE Emu, through the use of barcodes and web-based applications.
    • Size effect on the mineralogy and chemistry of Mytilus trossulus shells from the southern Baltic Sea: implications for environmental monitoring

      Piwoni-Piórewicz, A; Kukliński, P; Strekopytov, S; Humphreys-Williams, Emma; Najorka, J; Iglikowska, A (2017-04)
    • SEM-microphotogrammetry, a new take on an old method for generating high-resolution 3D models from SEM images

      Ball, AD; JOB, PA; WALKER, AEL (Wiley, 2017-03-22)
      The method we present here uses a scanning electron microscope programmed via macros to automatically capture dozens of images at suitable angles to generate accurate, detailed three‐dimensional (3D) surface models with micron‐scale resolution. We demonstrate that it is possible to use these Scanning Electron Microscope (SEM) images in conjunction with commercially available software originally developed for photogrammetry reconstructions from Digital Single Lens Reflex (DSLR) cameras and to reconstruct 3D models of the specimen. These 3D models can then be exported as polygon meshes and eventually 3D printed. This technique offers the potential to obtain data suitable to reconstruct very tiny features (e.g. diatoms, butterfly scales and mineral fabrics) at nanometre resolution. Ultimately, we foresee this as being a useful tool for better understanding spatial relationships at very high resolution. However, our motivation is also to use it to produce 3D models to be used in public outreach events and exhibitions, especially for the blind or partially sighted.
    • Conservation in a Barcode Age: A cross-discipline re-storage project for pyritic specimens

      Allington-Jones, L; Trafford, A (International Council of Museums, 2017-01-01)
      The dichotomy of conservation and access has long been recognised within the museum profession. The recent push for digitisation has added a new dimension to this argument: digital records can both increase potential access, due to increased awareness of the existence of objects, and decrease potential handling, since a more thorough awareness of an object creates a more informed decision regarding whether access is actually necessary. The use of barcodes and the creation of digital resources have therefore been incorporated into a re-storage project at the Natural History Museum, London to reduce duplication of work (and handling) by staff and to combat the reduction in access caused by the enclosure of objects within microenvironments, which in turn helps preserve specimens for future access. This project demonstrates how conservation and digitisation can successfully synthesise through the use of barcodes, when working with a cross-discipline team.
    • Hypervelocity impact in low earth orbit: finding subtle impactor signatures on the Hubble Space Telescope

      Kearsley, AT; Colaux, JL; Ross, DK; Wozniakiewicz, PL; Gerlach, L; Anz-Meador, P; Griffin, T; Reed, B; Opiela, J; Palitsin, VV; et al. (2017)