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Bergslagite, Ca2Be2As2O8(OH)2, is one of the only three known berylloarsenate minerals and is a member of the gadolinite supergroup. To date, very little is known about the thermal behavior of beryllium compounds and not much more about arsenates, while the thermal behavior of berylloarsenates (both natural and synthetic) has not been previously studied at all. In this work, the low and high-temperature behavior and thermal stability of bergslagite were studied in situ using single-crystal X-ray diffraction. Besides, its Raman spectrum was obtained and compared to the calculated one. Bergslagite does not undergo a phase transition in the temperature range − 173 to 700 °C, whereas it amorphizes at higher temperatures. The TO4-based (T = Be, As) framework remains stable, while the CaO6(OH)2 polyhedra are slightly expanding. The volume thermal expansion coefficient (32 × 10− 6 °C− 1) is comparable with borosilicate / beryllophosphate analogues (30–35 × 10− 6 °C− 1). The low thermal stability of bergslagite can be associated with the vacant octahedral position, which is occupied by divalent cations in more thermally stable beryllosilicate analogues. [ABSTRACT FROM AUTHOR]

Mineral assemblages formed at low oxygen fugacity are commonly confined to the lithologies of extraterrestrial or deep Earth origin. The occurrences of reduced mineral phases in upper crustal rocks [formed under oxygen fugacity conditions below the iron-wüstite (IW) buffer] are rare. However, they are important for understanding the chemical drivers of natural redox processes. Here, we present detailed studies of reduced mineral assemblages, which were found in situ in superficial combustion metamorphic (CM) rocks of west-central Jordan and compare them to reduced mineral assemblages found in situ in the CM rocks of south-central Israel. The studied assemblages contain a suite of exotic phases more typical of meteorites: native iron, phosphides (schreibersite, Fe3P; allabogdanite, Fe2P; transjordanite, Ni2P; murashkoite, FeP; halamishite, Ni5P4; zuktamrurite, FeP2; polekhovskyite, MoNiP2), and sulphides (daubréelite, FeCr2S4; oldhamite, CaS; troilite, FeS), part of which (native iron, allabogdanite, halamishite, polekhovskyite, daubréelite) have not previously been discovered in the CM rocks of west-central Jordan. The mineralogical diversity of terrestrial phosphides and the occurrence of Ni- / Mo-rich phases can be explained by (1) high P, Ni, and Mo content in the sedimentary protolith, (2) transformations of primary Fe3P / Fe2P, (3) extreme disequilibrium of the processes, and (4) crystal-chemical control of Ni- / Mo- speciation. [ABSTRACT FROM AUTHOR]

Orishchinite is a new terrestrial phosphide discovered in pyrometamorphic rocks of the Daba-Siwaqa combustion complex in West Jordan. The mineral occurs as an accessory phase in the fused clinopyroxene-plagioclase rock (paralava) texturally resembling gabbro-dolerite. Orishchinite forms resorbed equant grains up to 0.2 mm outrimmed with 0.1–0.2 thick zones of substituting murashkoite, FeP. Chemical composition (electron microprobe, wt%): Ni 38.49, Fe 22.38, Co 0.47, Mo 18.80, P 19.46, Total 99.60, corresponding to the empirical formula (Ni1.04Fe0.64Mo0.31Co0.01)Σ2.00P on the basis of 3 apfu. The simplified formula is (Ni,Fe,Mo)2P and the ideal one is Ni2P. Macroscopically, orishchinite grains have yellowish-white colour with metallic lustre. The mineral is brittle. In reflected light, orishchinite is yellowish-white and non-pleochroic. It is very weakly anisotropic (ΔR589 = 1.3%). Reflectance values for the wavelengths recommended by the Commission on Ore Mineralogy of the International Mineralogical Association are [Rmax/Rmin (%), λ (nm)]: 48.1/47.5, 470; 50.6/49.4, 546; 52.1/50.8, 589; 54.4/52.9.1, 650. The crystal structure was solved and refined to R1 = 0.016 based on 224 unique observed [I ≥ 2σ(I)] reflections. Orishchinite is orthorhombic, space group Pnma, a 5.8020(7), b 3.5933(4), c 6.7558(8) Å, V 140.85(3) Å3, Z = 4, Dx = 7.695 g cm-3. The strongest lines of the powder X-ray diffraction pattern [(d, Å) (I, %) (hkl)] are: 2.265(100)(112), 2.201(16)(202), 2.142(55)(211), 2.100(35)(103), 1.909(21)(013), 1.811(19)(113), 1.796(31)(020). Orishchinite is dimorphous with transjordanite (hexagonal Ni2P) and can be considered the Ni-dominant analogue of allabogdanite. [ABSTRACT FROM AUTHOR]

The present work focuses on the revealing the patterns of copper oxalates formation under the influence of lichens and fungi by combination of the results of field studies and model experiments. These findings create the scientific basis for the potential microbial technology applications (ore enrichment, monuments conservation, environment bioremediation, etc.). Copper oxalate moolooite Cu(C2O4)·H2O was discovered in saxicolous lichen Lecidea inops on the weathered chalcopyrite ore of Voronov Bor deposit (Central Karelia, Russia). Bioinspired syntheses of moolooite and wheatleyite Na2Cu(C2O4)2 2H2O with the participation of the microscopic fungi Aspergillus niger (active producer of oxalic acid) were carried out on weathered Cu-ore from the Voronov Bor deposit. It was shown that morphology of moolooite crystals is controlled both by the underlying rock and by the species composition of microorganisms. Iron ions (sourced from the underlying rock) in the crystallization medium inhibits the moolooite formation. The observed intensive dissolution of moolooite crystals are well explained by washing effect of the intratalline solutions which depends on repeatedly dehydration / rehydration cycles in the lichens. Joint interpretation of original and published data shows that moolooite along with other cooper oxalates are biominerals. [ABSTRACT FROM AUTHOR]

Murashkoite, FeP, is a new mineral found in pyrometamorphic rocks of the Hatrurim Formation, South Levant. It is a typical accessory phase in the marbles and paralavas in the southern Negev Desert, Israel and on the Transjordan Plateau, Jordan. Murashkoite occurs as grains and aggregates up to 2 mm closely associated with barringerite, (Fe,Ni)2P, and zuktamrurite, FeP2. The rock-forming minerals include pyroxenes of the diopside-hedenbergite series, anorthite with subordinate gehlenite, tridymite, cristobalite, pyrrhotite, fluorapatite, chromite, magnetite, hematite, merrillite and late hydrothermal carbonates, silicates and sulfates. Macroscopically, murashkoite is yellowish-grey in colour and has a metallic lustre. In reflected light, the mineral is white with a beige tint and it is non-pleochroic. The anisotropy is distinct, from yellow-grey to greyish-blue. Selected reflectance values [Rmax-Rmin, % (λ, nm)] are: 42.7-40.8 (400), 42.0-40.6 (500), 44.5-43.4 (600), 48.0-47.7 (700). It is brittle. VHN20 = 468 kg mm−2. The holotype material has the chemical composition (electron microprobe): Fe 63.82; Ni 0.88; P 35.56; total 100.26 wt.%. The empirical formula calculated on the basis of 2 apfu is (Fe0.99Ni0.01)1.00P1.00 corresponding to FeP. Murashkoite is orthorhombic, space group Pnma, unit cell parameters refined from the single-crystal data are: a 5.099(2), b 3.251(2), c 5.695(2) Å, V 94.41(8) Å3, Z = 4, Dx = 6.108(5) g cm−3. The crystal structure was solved and refined to R1 = 0.0305 on the basis of 131 unique reflections with I > 2σ(I). The strongest lines of the powder X-ray diffraction pattern [(d, Å) (I, %) (hkl)]: 2.831(75)(002,011); 2.548(22)(200); 2.477(46)(102,111); 1.975(47)(112); 1.895(100)(202,211); 1.779(19)(103); 1.632(45)(013,301,020). The mineral is named in honour of Dr. Mikhail Nikolaevich Murashko (born 1952), for his contributions to the mineralogy of the Hatrurim Formation. Murashkoite is a natural counterpart of synthetic FeP, the compound widely used in heterogeneous catalysis and electrocatalysis. [ABSTRACT FROM AUTHOR]

Zuktamrurite, FeP2, is a new mineral, a natural iron diphosphide found in the pyrometamorphic rocks of the Hatrurim Formation, in the southern part of the Negev Desert, Israel and on the Transjordan Plateau, Jordan. The mineral occurs as irregular grains up to 50 µm in size associated with murashkoite, FeP, and barringerite, (Fe,Ni)2P. In reflected light, zuktamrurite is white with a distinct bluish tint. It is non-pleochroic but exhibits distinct anisotropy in bluish colours. Reflectance values for the IMA COM recommended wavelengths are [Rmax/Rmin, % (λ, nm)]: 50.40/47.20 (470); 49.16/46.23 (546); 48.97/46.16 (589); 49.40/46.40 (650). It is brittle. Electron microprobe analysis of the holotype specimen gave the following chemical composition (wt%, average of 5 points): Fe 40.23; Ni 7.97; P 51.70; total 99.90. The empirical formula calculated on the basis of 3 apfu is (Fe0.86Ni0.16)1.02P1.98 corresponding to FeP2. Zuktamrurite is orthorhombic, space group Pnnm, unit cell parameters refined from the single-crystal data: a 4.9276(6), b 5.6460(7), c 2.8174(4) Å, V 78.38(1) Å3, Z = 2. Dx = 5.003 g cm−3. The crystal structure was solved and refined to R1 = 0.0121 on the basis of 109 unique reflections with I > 2σ(I). The strongest lines of the powder X-ray diffraction pattern [(d, Å) (I, %) (hkl)]: 3.714 (54) (110); 2.820 (31) (020); 2.451 (100) (120, 101); 2.242 (55) (111); 1.760 (37) (211). The mineral is named for the Zuk-Tamrur cliff (Dead Sea) located nearby the type locality, the Halamish Wadi, southern Negev Desert, Israel. Zuktamrurite is the phosphide analogue of löllingite (loellingite), FeAs2. It is the most phosphorus-rich phosphide ever found in nature. [ABSTRACT FROM AUTHOR]

The chemical and mineral composition and formation conditions of dense grey-yellow colour crusts on the surface of monuments and bowls of decorative fountains in Peterhof (Russia) were studied using a wide range of methods (XRD, SEM, EMPA, Raman spectroscopy). The crusts consisted of calcium carbonates (monohydrocalcite, aragonite, calcite), magnesium carbonates (lansfordite, nesquehonite), and Sr-, Pb-rich carbonates (aragonite-cerussite-strontianite solid solution; up to 29 wt% PbO and 43 wt% SrO). Carbonates formed on all types of materials (gold, polyester resin, marble, granite) and do not interact with it. The cause of the formation of carbonate crusts on decorative fountains is the high content of carbonate ions in water. The variety of mineral phases is associated with fluctuations in the pH and Mg/Ca ratio. Recommendations are given on conservation measures that inhibit the formation of carbonate layers that threaten the preservation of the cultural heritage of this UNESCO World Heritage Site. [ABSTRACT FROM AUTHOR]

Zuktamrurite, FeP2, is a new mineral, a natural iron diphosphide found in the pyrometamorphic rocks of the Hatrurim Formation, in the southern part of the Negev Desert, Israel and on the Transjordan Plateau, Jordan. The mineral occurs as irregular grains up to 50 µm in size associated with murashkoite, FeP, and barringerite, (Fe,Ni)2P. In reflected light, zuktamrurite is white with a distinct bluish tint. It is non-pleochroic but exhibits distinct anisotropy in bluish colours. Reflectance values for the IMA COM recommended wavelengths are [Rmax/Rmin, % (λ, nm)]: 50.40/47.20 (470); 49.16/46.23 (546); 48.97/46.16 (589); 49.40/46.40 (650). It is brittle. Electron microprobe analysis of the holotype specimen gave the following chemical composition (wt%, average of 5 points): Fe 40.23; Ni 7.97; P 51.70; total 99.90. The empirical formula calculated on the basis of 3 apfu is (Fe0.86Ni0.16)1.02P1.98 corresponding to FeP2. Zuktamrurite is orthorhombic, space group Pnnm, unit cell parameters refined from the single-crystal data: a 4.9276(6), b 5.6460(7), c 2.8174(4) Å, V 78.38(1) Å3, Z = 2. Dx = 5.003 g cm−3. The crystal structure was solved and refined to R1 = 0.0121 on the basis of 109 unique reflections with I > 2σ(I). The strongest lines of the powder X-ray diffraction pattern [(d, Å) (I, %) (hkl)]: 3.714 (54) (110); 2.820 (31) (020); 2.451 (100) (120, 101); 2.242 (55) (111); 1.760 (37) (211). The mineral is named for the Zuk-Tamrur cliff (Dead Sea) located nearby the type locality, the Halamish Wadi, southern Negev Desert, Israel. Zuktamrurite is the phosphide analogue of löllingite (loellingite), FeAs2. It is the most phosphorus-rich phosphide ever found in nature. [ABSTRACT FROM AUTHOR]