Physics and Chemistry of Minerals最新文献

{"title":"Hydrothermal synthesis and formation of a synthetic analogue of reichenbachite, Cu5(PO4)2(OH)4","authors":"Marley E. J. Knight,&nbsp;Sian E. Woodfine,&nbsp;Richard J. Darton","doi":"10.1007/s00269-026-01347-x","DOIUrl":"10.1007/s00269-026-01347-x","url":null,"abstract":"<div>\u0000 \u0000 <p>Reichenbachite (Cu₅(PO₄)₂(OH)₄) is a rare copper-hydroxy-phosphate, the synthetic accessibility and phase evolution of which are still poorly understood. Here we report the first known reproducible hydrothermal synthesis to yield high purity reichenbachite, facilitated by alkaline conditions at 180 °C. Systematic time-controlled experiments clearly reveal a kinetic-thermodynamic bias: pseudomalachite forms rapidly as the metastable kinetic phase and reichenbachite emerges as the thermodynamic product after extended reaction times. Powder X-ray diffraction experiments combined with Rietveld refinements confirm phase selectivity as an outcome of reaction conditions. Scanning electron microscopy shows characteristic morphological features of each polymorph. Through a combination of order–disorder theory, classical nucleation theory, and Ostwald’s rule of stages we propose a mechanism of formation through polymorphic interconversion driven by synthesis duration and alkalinity. This study not only establishes a new reproducible synthesis for a previously elusive mineral but also provides insights into fundamental metastable-equilibrium phase transitions in copper hydroxy-phosphate systems, with implications for crystal growth theory and design of functional phosphate-materials.</p>\u0000 </div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00269-026-01347-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147607260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Equation of state of nitrogen-bearing K-cymrite","authors":"Alexandr V. Romanenko,&nbsp;Sergey V. Rashchenko,&nbsp;Alexander G. Sokol,&nbsp;Andrey V. Korsakov","doi":"10.1007/s00269-026-01346-y","DOIUrl":"10.1007/s00269-026-01346-y","url":null,"abstract":"<div>\u0000 \u0000 <p>Nitrogen-bearing K-cymrite (K, NH₄)AlSi₃O₈·(N₂,NH₃,H₂O), a clathrate phase that is stable in subduction zones, may play a crucial role in transporting potassium, water, and nitrogen to the depths of the mantle. Synchrotron X-ray diffraction in a diamond anvil cell with a methanol-ethanol medium was used to study its compressibility up to 10 GPa. N-bearing K-cymrite retains its hexagonal <i>P</i>6/<i>mmm</i> symmetry without signs of phase transitions across the pressure range. The third-order Birch-Murnaghan equation of state yielded the following values: <i>V</i>₀ = 191.38(3) ų, <i>K</i>₀ = 47.1(2) GPa, and <i>K</i>₀’ = 6.40(7). Unlike K-cymrite KAlSi₃O₈·H₂O, which develops incommensurate modulation above 7–8 GPa, no satellite reflections appear in the diffraction patterns of N-bearing K-cymrite, even at 16 GPa. This suggests that N₂ stabilizes the double tetrahedral layers against wave-like bending.</p>\u0000 </div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Equation of state and structural variations of synthetic forsterite-fayalite solid solution by single-crystal X-ray diffraction","authors":"Zhilin Ye,&nbsp;Jingui Xu,&nbsp;Dongzhou Zhang,&nbsp;Weiyi Liu,&nbsp;Wenge Zhou,&nbsp;Dawei Fan","doi":"10.1007/s00269-026-01341-3","DOIUrl":"10.1007/s00269-026-01341-3","url":null,"abstract":"<div>\u0000 \u0000 <p>Olivine, a predominant mineral in the Earth’s upper mantle, plays a crucial role in geophysical and geochemical processes due to its abundance and elastic characteristics. This study investigates the elastic properties and structural variations of synthetic forsterite-fayalite solid solutions under high-pressure conditions through synchrotron single-crystal X-ray diffraction. A series of samples with varying fayalite contents were synthesized and characterized to evaluate the impact of Fe incorporation on unit-cell parameters, bulk modulus, and compression behavior. The results demonstrate that increasing fayalite content elongates the <i>b</i>-axis, increases polyhedral distortions, and enhances the bulk modulus, while maintaining the structural rigidity of [SiO₄] tetrahedra. By refining the fit parameters of the Birch-Murnaghan equation of state, this study establishes a composition-property relationship for elastic behavior. These results provide key constraints for modeling mantle dynamics and planetary evolution.</p>\u0000 </div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147561258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New insights of origin determination and formation of emeralds from Afghanistan (Panjshir Valley) and Pakistan (Swat Valley): constraints from spectroscopy and LA-ICP-MS test","authors":"Zhiyi Zhang,&nbsp;Bo Xu,&nbsp;Siyi Zhao","doi":"10.1007/s00269-026-01343-1","DOIUrl":"10.1007/s00269-026-01343-1","url":null,"abstract":"<div><p>The identification of the geographic origin of emeralds constitutes a crucial technique in gemological laboratories and holds a prominent position as a research focus within the gemology field. The proximity of the emerald deposits in Panjshir Valley, Afghanistan, and Swat Valley, Pakistan (just 250 km apart) and their shared formation age of 23 Ma pose significant challenges in distinguishing the origins of the emeralds from these two locations. Furthermore, the mineralization patterns of the emeralds from these two sites are not yet fully understood. The inclusion, spectroscopy characteristics and chemical composition of emeralds from these two deposits were systematically analyzed in this study through basic gemological tests, spectroscopic tests (infrared, UV-VIS-NIR and Raman spectroscopy), and major and trace element tests (LA-ICP-MS). There are a greater variety of inclusions in Pakistani emeralds, and that pyrite stands out as the most common inclusion found in emeralds from both sources. The patterns and frequencies of infrared and UV-VIS-NIR spectra of emeralds from the two deposits exhibit considerable promise for identifying their origins. As for the genesis of the two deposits, the low Li, Rb, and Cs contents of emeralds from both localities suggest that the ore-forming fluid was of metamorphic origin. The high Sc content of both is related to albitization of host rocks (Panjshir Valley) and deep hidden leucogranite (Swat Valley). This study provides an appropriate case for the origin identification by spectroscopic characteristics, proposes the element content standard for testing the source of ore-forming fluid, and verifies the geological characteristics of the two deposits through the element content.</p></div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147441886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"‌ Impact of minor aluminum incorporation on the high-pressure properties of stishovite","authors":"Shuo Qu,&nbsp;Yuhui Jiang,&nbsp;Li Zhang,&nbsp;Peiyan Wu,&nbsp;Xiaofeng Lu,&nbsp;Jinpu Liu","doi":"10.1007/s00269-026-01344-0","DOIUrl":"10.1007/s00269-026-01344-0","url":null,"abstract":"<div>\u0000 \u0000 <p>Stishovite is a key constituent of subducting oceanic crust. Outside the stability fields of dense hydrous magnesium silicates, it remains stable in high-temperature regions of the deep mantle and serves as a significant reservoir for hydrogen. Numerous studies show that stishovite can incorporate over 3 wt% Al₂O₃, which can significantly lower the pressure required for the stishovite-to-post-stishovite phase transition. However, the stability of Al-rich stishovite under typical upper-mantle P-T conditions remains uncertain. Furthermore, the effect of even minor Al contents on this transition pressure requires further investigation. In this study, high-pressure and high-temperature synthesis experiments of Al-bearing stishovite were conducted at 11 GPa and 1300 °C under hydrous conditions. The results show no evidence for the existence of Al-rich stishovite in the base of the upper mantle. Furthermore, in situ high-pressure Raman spectroscopy performed on synthesized low-Al stishovite samples (up to 42 GPa at room temperature) reveals that the presence of a small amount of aluminum (1.41–1.57 wt% Al₂O₃) in stishovite reduces the pressure required for the stishovite–post-stishovite phase transition by at least 20 GPa. Compared to aluminum, hydrogen do not significantly affect this phase transition.</p>\u0000 </div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147441885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural disorder in Fe-bearing topaz-OH revealed by single-crystal X-ray diffraction","authors":"Baoyun Wang,&nbsp;Meisu Xiang","doi":"10.1007/s00269-026-01342-2","DOIUrl":"10.1007/s00269-026-01342-2","url":null,"abstract":"<div><p>Topaz-OH phases, including structurally distinct but chemically identical topaz-OH I and topaz-OH II, are considered as potential water carriers in hydrated subducted sediments. In this study, Fe-bearing topaz-OH I was synthesized at 15.5 GPa and 1400 °C, with a chemical composition of Al_1.94±0.05Fe_0.18±0.01Si_0.69±0.02O₆H_2.88±0.13. Its crystal structure is similar to that of the ordered Al-endmember topaz-OH I (Al₂SiO₆H₂), with both exhibiting the same <i>Pbnm</i> space group and comparable unit cell parameters. However, this structure contains evident vacancies in the tetrahedral sites and new occupied octahedral sites that are normally vacant in the ordered Al-endmember topaz-OH I. Our structural model represents a transitional phase between the Al/Si-ordered topaz-OH I and the fully Al/Si-disordered topaz-OH II. These findings suggest that structural disorder may play a key role in influencing the tetrahedral-to-octahedral occupancy ratio, the evolution of crystal structures, and the thermal stability of topaz-OH under the high pressure-temperature conditions of the deep mantle.</p></div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147441887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linking feldspar luminescence phenomena and mineralogy using spatially resolved techniques","authors":"Svenja Riedesel,&nbsp;Geoff A. T. Duller,&nbsp;Max Hellers,&nbsp;Nick J. G. Pearce,&nbsp;Joseph A. Winzar,&nbsp;Anthony M. T. Bell,&nbsp;Reiner Kleinschrodt","doi":"10.1007/s00269-026-01345-z","DOIUrl":"10.1007/s00269-026-01345-z","url":null,"abstract":"<div><p>Feldspars, the most abundant mineral group in the Earth’s crust, exhibit a striking chemical and structural variety resulting from variations in their crystallisation environments and post-crystallisation processes. Since feldspars record both formation and alteration processes and conditions, they are key components in geological studies and valuable for developing tools to reconstruct past environmental change. Thermally and optically stimulated luminescence, the ability of minerals, such as feldspars, to emit light in different wavelengths upon excitation with light or heat, are sensitive to changes in the crystal lattice and thus may have the potential to be used as a tool for identifying crystallisation and alteration processes affecting feldspars. So far, the luminescence of feldspars has primarily been used as a numerical geochronological dating technique, constraining past geological and archaeological events and processes. However, the sensitivity of feldspar luminescence signals to changes in crystallisation and post-crystallisation processes allows for the development of luminescence-based proxies beyond geochronological studies.</p><p>This study investigates the relationship between luminescence emission intensities in three emission bands and mineralogical features in 13 alkali feldspars and plagioclases using spatially resolved luminescence techniques, electron microprobe analysis, bulk geochemistry, and X-ray powder diffraction. The intensity of infrared photoluminescence (IRPL) emission (~ 900 and ~ 950 nm) is particularly sensitive to chemical and structural heterogeneities within the feldspar samples, such as the presence of K-rich phases, fractures, and alteration products. Blue (~ 400 nm) thermoluminescence (TL) and infrared stimulated luminescence (IRSL) emission intensities vary with feldspar type and perthitic texture, while yellow-green (~ 560 nm) TL and IRSL emissions are linked to fluid-induced alteration of the feldspar chemistry and structure. These findings highlight the potential of spatially resolved luminescence measurements as a non-destructive tool for identifying crystallisation and alteration processes in feldspars, as well as relationships between luminescence signal intensity and mineralogical properties, advancing both geochronological techniques which use these emissions, and mineralogical studies.</p></div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00269-026-01345-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147441212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Alloyed cementite (Fe–Ni–Cr)3C: structure and hyperfine field from DFT calculations and experimental comparison","authors":"L. V. Dobysheva","doi":"10.1007/s00269-026-01340-4","DOIUrl":"10.1007/s00269-026-01340-4","url":null,"abstract":"<div>\u0000 \u0000 <p>The alloying elements introduced into carbon steel to enhance its mechanical properties also diffuse into cementite (Fe₃C) particles, modifying their characteristics and thereby influencing the overall performance of the steel. This study employs density functional theory (DFT) calculations to investigate cementite doped with Ni and Cr which exhibit contrasting effects. The preferred lattice sites of impurity atoms were determined through a comparison of calculated and experimental structural parameters. The formation mechanism of the hyperfine magnetic field (HFF) and its correlation with atomic magnetic moments were systematically investigated. The validity of common approximations in Mössbauer spectroscopy analysis was evaluated for the cementite system. HFF distribution functions were modeled using calculated values and compared with experiments.</p>\u0000 </div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147336520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atomic-scale deformation mechanisms at high-pressure in hydroboracite, CaMg[B₃O₄(OH)₃]₂·3H₂O","authors":"Davide Comboni,&nbsp;Paolo Lotti,&nbsp;Lisa Chiappella,&nbsp;Tommaso Battiston,&nbsp;Gaston Garbarino,&nbsp;Paola Giura,&nbsp;G. Diego Gatta","doi":"10.1007/s00269-026-01339-x","DOIUrl":"10.1007/s00269-026-01339-x","url":null,"abstract":"<div><p>The high-pressure behaviour of hydroboracite [ideally CaMg[B₃O₄(OH)₃]₂·3H₂O, Sp. Gr. <i>P</i>2<i>/c</i> with <i>a</i> ~ 11.769, <i>b</i> ~ 6.684, <i>c</i> ~ 8.235 Å, and <i>β</i> ~ 102.6° at room conditions] has been studied by two <i>in-situ</i> single-crystal synchrotron X-ray diffraction experiments up to about 15 GPa, using He as pressure-transmitting medium. Between 14.51(5) and 14.72(5) GPa, hydroboracite undergoes a first-order phase transition to its high-pressure polymorph, hydroboracite-II (likely monoclinic with <i>a</i> ~ 11.29, <i>b</i> ~ 6.297, <i>c</i> ~ 7.48 Å, and <i>β</i> ~ 106°, space group unknown). The isothermal bulk modulus (<i>K</i>_<i>V</i>0 = β⁻¹_{<i>P</i>0,<i>T</i>0}, where β_{<i>P</i>0,<i>T</i>0} is the volume compressibility coefficient) of hydroboracite was found to be <i>K</i>_<i>V</i>0 = 41.4(6) GPa. The destructive nature of the phase transition prevented any structure resolution of hydroboracite-II or even the continuation of the experiments at pressures higher than 15.45(5) GPa. In the pressure range 0–14.45(5) GPa, the compressional anisotropy of hydroboracite, indicated by the ratio between the principal components of the unit-strain ellipsoid, is ε₁:ε₂:ε₃ = 2.2:1.3:1. The <i>P</i>-induced deformation mechanisms at the atomic scale in hydroboracite are here described.</p></div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147342227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of ball-milling and thermal environment on the structural and thermal stability of antigorite serpentine: Sr(^{2+}) adsorption and thermal expansion","authors":"Meenu Prasher,&nbsp;Rohan Phatak,&nbsp;Mohit Rattanpal,&nbsp;Abhijit Ghosh,&nbsp;Mohammad Yunus,&nbsp;Naina Raje,&nbsp;Harshala J. Parab,&nbsp;Pranesh Sengupta","doi":"10.1007/s00269-025-01337-5","DOIUrl":"10.1007/s00269-025-01337-5","url":null,"abstract":"<div>\u0000 \u0000 <p>The thermal and structural stability of serpentine is critical in determining its potential applications as concrete aggregate in deep geological repositories for nuclear waste disposal. This study investigates how ball milling and the thermal environment, specifically oxidizing and inert conditions, influence structural and thermal stability of antigorite serpentine. We show that prolonged ball milling of the antigorite disrupts its silicon tetrahedral sheet, leading to increased disorder in the (001) plane and collapse of the layered structure along the c-axis. Ball milling enhances the Sr<span>(^{2+})</span> adsorption by antigorite, where early milling promotes a physisorption-dominated regime linked to BET-accessible surface area, whereas prolonged milling shifts Sr<span>(^{2+})</span> uptake into a chemisorption regime governed by defect-rich, high-energy sites. We also find that antigorite exhibits better thermal stability against dehydroxylation in the air atmosphere than in the inert atmosphere. One of the key findings is that the thermal expansion coefficient of antigorite along the c-axis in the oxidizing air atmosphere (1.22 <span>(times )</span> 10<span>(^{-5})</span> ±4.28<span>(times )</span>10<span>(^{-7})</span> <span>(^{circ })</span>C<span>(^{-1})</span>) is an order of magnitude lower than in an inert argon atmosphere (1.39<span>(times )</span>10<span>(^{-4})</span> ±3.39<span>(times )</span>10<span>(^{-6})</span> <span>(^{circ })</span>C<span>(^{-1})</span>). The observed effects of thermal environment are explained in the light of Fe<span>(^{2+})</span> <span>(rightarrow )</span> Fe<span>(^{3+})</span> oxidation potential, supported by the X-ray photoelectron spectroscopy (XPS) measurements. Overall, the findings highlight the pivotal role of mechanochemical activation and thermal environment in governing the stability of antigorite, providing valuable insights into the underlying mechanisms driving its structural and chemical transformation.</p>\u0000 </div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"53 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}