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(1) Background: The Gulf of Aqaba (GoA) supports unique and diverse marine ecosystems. It is one of the highest anthropogenically impacted coasts in the Middle East region, where rapid human activities are likely to degrade these naturally diverse but stressed ecosystems. (2) Methods: Various water quality parameters were measured to assess the current status and conditions of GoA seawater including pH, total dissolved solids (TDS), total alkalinity (TA), Cl⁻, NO₃⁻, SO₄²⁻, PO₄³⁻, NH₄⁺, Ca²⁺, Mg²⁺, Na⁺, K⁺, Sr, Cd, Co, Cr, Cu, Fe, Mn, Pb, and Zn. (3) Results: The pH values indicated basic coastal waters. The elevated levels of TDS with an average of about 42 g/L indicated highly saline conditions. Relatively low levels of inorganic nutrients were observed consistent with the prevalence of oligotrophic conditions in GoA seawater. The concentrations of Ca²⁺, Mg²⁺, Na⁺, K⁺, Sr, Cl⁻, and SO₄²⁻ in surface layer varied spatially from about 423–487, 2246–2356, 9542–12,647, 513–713, 9.2–10.4, 22,173–25,992, and 317–407 mg/L, respectively. The average levels of Cd, Co, Cr, Cu, Fe, Mn, Pb and Zn ranged from 0.51, 0.38, 1.44, 1.29, 0.88, 0.38, and 6.05 µg/L, respectively. (4) Conclusions: The prevailing saline conditions of high temperatures, high evaporation rates, the water stratification and intense dust storms are major contributing factors to the observed seawater chemistry. The surface distribution of water quality variables showed spatial variations with no specific patterns, except for metal contents which exhibited southward increasing trends, closed to the industrial complex. The vast majority of these quality parameters showed relatively higher values compared to those of other regions. Full article

Rare type of silicate inclusions found in the Elga iron meteorite (group IIE) has a very specific mineral composition and shows silicate (≈90%)–natrophosphate (≈10%) liquid immiscibility due to meniscus-like isolation of Na-Ca-Mg-Fe phosphates. The 3 mm wide immiscible inclusion has been first studied in detail using optical microscopy, scanning electron microscopy, electron microprobe analysis and Raman spectroscopy. The silicate part of the inclusion contains fine-grained quartz-feldspar aggregate and mafic minerals. The relationships of feldspars indicate solid decay of initially homogenous K-Na-feldspar into albite and K-feldspar with decreasing of temperature. Some mafic minerals in the silicate part are exotic in composition: the dominant phase is an obertiite-subgroup oxyamphibole (amphibole supergroup), varying from ferri-obertiite NaNa₂Mg₃Fe³⁺Ti[Si₈O₂₂]O₂ to hypothetical NaNa₂Mg₃Fe²⁺_0.5Ti_1.5[Si₈O₂₂]O₂; minor phases are the aenigmatite-subgroup mineral (sapphirine supergroup) with composition close to median value of the Na₂Fe²⁺₅TiSi₆O₁₈O₂-Na₂Mg₅TiSi₆O₁₈O₂ join, orthopyroxene (enstatite), clinopyroxene of the diopside Ca(Mg,Fe)Si₂O₆–kosmochlor NaCrSi₂O₆-Na(Mg,Fe)_0.5Ti_0.5Si₂O₆ series and chromite. The alteration phases are represented by Fe-dominant chlorite, goethite and hydrated Na₂O-rich (2.3–3.3 wt.%) Fe-phosphate close to vivianite. Natrophosphate part consists of aggregate of three orthophosphates (brianite, czochralskiite, marićite) and minor Na-Cr-Ti-clinopyroxene, pentlandite, rarely taenite. Czochralskiite Na₄Ca₃Mg(PO₄)₄ is rich in FeO (2.3–5.1 wt.%) and MnO (0.4–1.5 wt.%). Brianite Na₂CaMg(PO₄)₂ contains FeO (3.0–4.3 wt.%) and MnO (0.3–0.7 wt.%) and marićite NaFe(PO₄) bears MnO (5.5–6.2 wt.%), MgO (5.3–6.2 wt.%) and CaO (0.5–1.5 wt.%). The contact between immiscible parts is decorated by enstatite zone in the silicate part and diopside–kosmochlor clinopyroxene zone in the natrophosphate ones. The mineralogy of the studied immiscible inclusion outlines three potentially new mineral species, which were first identified in meteorites: obertiite–related oxyamphibole NaNa₂Mg₃Fe²⁺_0.5Ti_1.5[Si₈O₂₂]O₂, Mg-analog of aenigmatite Na₂Mg₅TiSi₆O₁₈O₂ and Na-Ti-rich clinopyroxene Na(Mg,Fe)_0.5Ti_0.5Si₂O₆. Full article

Xenophyllite, ideally Na₄Fe₇(PO₄)₆, is a rare meteoritic phosphate found in phosphide-phosphate assemblages confined to troilite nodules of the Augustinovka iron meteorite (medium octahedrite, IIIAB). The mineral occurs as tiny lamella up to 0.15 mm long cross-cutting millimeter-sized grains of sarcopside, Fe₃(PO₄)₂, associated with schreibersite, chromite and pentlandite. Xenophyllite is translucent, has a bluish-green to grey-green color and vitreous lustre. Moh’s hardness is 3.5–4. Cleavage is perfect on {001}. Measured density is 3.58(5) g/cm³. The mineral is biaxial (−), 2V 10–20°, with refractive indexes: α 1.675(2), β 1.681(2), γ 1.681 (2). Chemical composition of the holotype specimen (electron microprobe, wt.%) is: Na₂O 10.9, K₂O 0.4, MnO 5.8, FeO 42.1, Cr₂O₃ 0.8, P₂O₅ 40.7, total 100.7, corresponding to the empirical formula (Na_3.67K_0.09)_Σ3.76(Fe²⁺_6.12Mn²⁺_0.85Cr_0.11)_Σ7.08P_5.99O_24.00. Xenophyllite is triclinic, P1 or P-1, a 9.643(6), b 9.633(5), c 17.645(11) Å; α 88.26(5), β 88.16(5), γ 64.83(5)°, V 1482(2) ų, Z = 3. The toichiome C-centered subcell has the following dimensions: a 16.257(9), b 10.318(8), c 6.257(9) Å, β = 112.77(9)°, V 968(2) ų, Z = 2. Xenophyllite is structurally related to synthetic phosphate Kna₃Fe₇(PO₄)₆ having a channel-type structure, and galileiite, NaFe₄(PO₄)₃. The variations of chemical composition of xenophyllite ranging from Na₄Fe₇(PO₄)₆ to almost Na₂Fe₈(PO₄)₆ are accounted for by Na-ions mobility. The latter property makes xenophyllite a promising prototype for cathode materials used in sodium-ion batteries. Full article

This work assessed the groundwater hydrogeochemistry and the drinking water quality of 10 wells supplying the urban area of Zamora, Michoacán, Mexico. Two sampling campaigns were conducted in May 2018 (dry season) and November 2018 (wet season) to describe the chemistry of the water and its interaction with the rock. Physical and chemical constituents (temperature, pH, electrical conductivity, color, turbidity, solids, total hardness, total alkalinity, chemical and biochemical oxygen demands), major components (Ca²⁺, Mg²⁺, Na⁺, K⁺, SO₄²⁻, PO₄³⁻, HCO₃⁻, CO₃²⁻, Cl⁻, N-NO₃⁻, and N-NH₃), as well as trace elements (As, Fe, Mn, Ba, Al, Sb, Co, V, Cu, Cd, Cr, Ni, Zn, Tl, Pb) were analyzed. Results showed groundwater with a slight tendency to alkalinity. The hydrogeochemical facies observed are Ca²⁺-HCO₃⁻ in all sites. Hydrochemical diagrams indicate immature, cold, non-saline, and uncontaminated water with short residence time. Water–rock interaction predominates. The water in the study area is appropriate for drinking use according to Mexican and international regulations with an excellent quality in 7 wells and good in the other 3. Full article