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In this study, the garnet-type Yb 3 Al 5 O 12 coating was fabricated by atmospheric plasma spraying and its properties were systematically investigated. Results show the as-sprayed coating consists of crystalline Yb 3 Al 5 O 12 with amorphous phase, recrystallization occurs at 918.5 °C accompanied by a 0.32% volume shrinkage. Yb 3 Al 5 O 12 coating demonstrates low thermal conductivity (2.1 W/(m∙K) at 1000 °C) coupled with a moderate thermal expansion coefficient (8.87 × 10−6 K−1 from 200 °C to 1400 °C). Additionally, Yb 3 Al 5 O 12 coating displays remarkable structure stability and sintering resistance at elevated temperatures. Its robust corrosion resistance can be demonstrated by rapidly generating dense anorthite layers during CMAS corrosion and the lack of a discernible corrosion layer in water vapor corrosion. Yb 3 Al 5 O 12 /YSZ TBC undertakes a thermal cycling lifetime of 970 cycles, superior to YSZ of 764 cycles. This improvement is primarily ascribed to lower oxygen permeability of garnet layer. These preliminary results indicate that Yb 3 Al 5 O 12 coating might be suitable for advanced TBC applications. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. The list includes various papers on topics such as molecular packing characteristics, crystal structures, photocatalytic activity, crystal growth, and more. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document also mentions approved training courses offered by the society. [Extracted from the article]

The rapid development of kilowatt-level lasers is in urgent need of excellent magneto-optical materials for Faraday isolators. In this work, a new component Tb3Al2Ga3O12 crystal was designed to meet applications in high-power lasers. A high-quality single crystal has been successfully obtained by the Czochralski technique. The Tb3Al2Ga3O12 crystal is verified to have high crystallinity with a small full width at half maximum (FWHM) of 43.2′′ and exhibits excellent uniformity, especially enhanced magneto-optical properties, exceeding ∼7–15% that of the traditional TGG crystal. These excellent attributes suggest that the Tb3Al2Ga3O12 crystal can be a promising candidate for Faraday isolators. [ABSTRACT FROM AUTHOR]

High-temperature sintering is crucial to achieve good crystallinity and fast-ion conduction in oxide-type solid-electrolytes such as lithium garnets, NASICONs and LISICONs, leading to stiff ceramics which are difficult to integrate in all-solid-state batteries. Developing conventional oxide-based solid-electrolytes in deformable forms that maintain good ion transport properties and allow facile formulation of bulk-type solid-state batteries, hence, remains a challenge. Here, a new γ-Li3PO4/GeO2 composite, that adopts a novel nanostructured architecture and retains deformability after calcination at 500 °C, is successfully synthesized and densified by cold-pressing. Cold-pressed pellets of the new composite showed an ion conductivity that is four orders of magnitude higher than that of the parent γ-Li3PO4 and comparable to those of high-temperature stiff Li3+xP1−xGexO4 ceramics. The γ-Li3PO4/GeO2 composite is stable against high voltages (up to 5 V vs Li+/Li), which suggests a safe use in contact with high-voltage cathodes. The new composite can also be modified to serve as an active anode layer in solid-state cells due to the electrochemical activity of GeO2 at low voltages (<1 V vs. Li+/Li). This study emphasizes the potential of using low-temperature synthesis to develop novel oxide-based nanoarchitectures for all-solid-state battery applications. [ABSTRACT FROM AUTHOR]

Post-orogenic magmatism is uncommon in the Songpan-Ganze Orogen (SGO), and could provide deep insights into geodynamic evolution and related metallogenesis. Here we present zircon U-Pb-Hf isotopes and whole-rock geochemical data, for post-orogenic granitoids newly identified in the southern SGO. The Longxigou and Yangfanggou granites yield crystallization age of ca. 165 Ma and εHf(t) values of +3.8 to −9.1. This age post-dates regional ca. 220–200 Ma orogenic magmatism and ca. 205–190 Ma peak metamorphism, and corresponds to ca. 200–150 Ma post-orogenic magmatism which is exemplified by neighbouring and coeval Wenjiaping and Wulaxi felsic plutons. They are crosscut by ca. 133 Ma granitic pegmatites, with εHf(t) values of −4.3 to −14.2. These post-orogenic granites show high SiO2 contents, as well as low Mg# values, (Zr + Nb + Ce + Y) concentrations and zircon saturation temperatures. They have continental crust-like REE patterns and trace element profiles, and exhibit negative Eu anomalies, enrichment in large ion lithophile elements and depletion in high field strength elements. Their mineral assemblages lack typical high-temperature (e.g. pyroxene and fayalite) and peraluminous (e.g. garnet and cordierite) varieties. All these features indicate an I-type granite affinity, and a dominant derivation from thickened lower crust. In comparison, these post-orogenic granites are compositionally distinct from regional late-orogenic (>200 Ma) categories, which have more positive εHf(t) values and higher Mg# values, with subduction-related signatures involving significant mantle components. Further, several high-grade stratiform Cu deposits and a tungsten deposit occur to the south of these granitic plutons, and have mineralization ages of 164–151 Ma together with biotite alteration age of ca. 134 Ma. Hence, ca. 165–133 Ma magmatic-hydrothermal system was most likely responsible for Cu-W mineralization and effective upgrading of metal deposits in the southern SGO. [ABSTRACT FROM AUTHOR]

Garnet peridotite xenoliths have been rarely reported from suboceanic mantle. Petrographic and geochemical characteristics of garnet-bearing oceanic peridotite xenoliths provide precious information on dynamics of the suboceanic lithosphere and asthenosphere interaction. We examined a lherzolite xenolith included in olivine nephelinite lava from Aitutaki Island, a member of the Cook-Austral volcanic chain. The lherzolite xenolith contains reddish fine-grained (< 5 µm in size) mineral aggregates (FMAs) with size range of 0.5–6 mm, consisting of olivine, calcic and sodic plagioclases, aluminous spinel, native iron, and nepheline. Microstructural observations and chemical data corroborate that the FMA is a decomposed pyrope-rich garnet including chromian spinel grains with an irregular highly indented morphology in the center. The FMA is surrounded by pyroxene-poor and olivine-rich aureole. The spatial and morphological relationships of FMA and chromian spinel with pyroxene-depleted margin suggest a reaction of aluminous spinel + pyroxenes → pyrope-rich garnet + olivine, which requires a compression before decomposition of the garnet to FMA. An orthopyroxene grain shows slight but clear chemical zoning characterized by increase in Al, Ca, and Cr from the grain center to the rim. The zoning patterns of Al and Ca in the orthopyroxene grain can be modeled by diffusion-controlled solid-state reactions induced by pressure and temperature changes, keeping surface concentrations in equilibrium with the other coexisting mineral phases. The results indicate that the mantle, from which the lherzolite xenolith was derived, underwent isothermal decompression followed by a weak heating on a time scale of a few tenths of million years before the xenolith extraction. From the deduced compression and decompression histories, we hypothesize that the mantle beneath Aitutaki Island was once dragged down to a garnet-stable deep mantle region and brought up later by small-scale sublithospheric convection. [ABSTRACT FROM AUTHOR]

The advent of Ni‐rich cathode promises to increase their energy density of lithium (Li) ion batteries. However, the inherent catalytic activity and resultant decomposition products deteriorate the interfacial stability of Ni‐rich cathode. This case is further exacerbated by a higher operation voltage for delivering more capacity. Here, a facile strategy is reported for coating garnet solid electrolyte as a corrosion inhibiting layer for Ni‐rich cathode, aiming to establish an efficient Li‐conducting and stable interface that reinforces the Li transport and withstands the HF attack, respectively. Benefiting from this design, the interface of modified Ni‐rich cathode exhibits less polarization and fewer side reactions even at a cut‐off voltage of 4.7 V. This difference is mainly attributed to the fast Li transport stemming from the compatibility between Ni‐rich cathode and garnet solid electrolyte. Meanwhile, the stable and dense cathode electrolyte layer, observed by cryo‐transmission electron microscopy characterization, inhibits side reaction between Ni‐rich cathode and liquid electrolyte. This work provides an effective strategy to reinforce the interfacial stability of Ni‐rich cathode and has the potential to advance the commercialization of Ni‐rich cathodes. [ABSTRACT FROM AUTHOR]

Olivine from Southeast Vietnam is notable for its dark brown colour, rather than the yellowish green appearance exhibited by typical gem-quality peridot. Discovered in 2020, this material occurs as xenocrysts weathered from the Xuan Loc alkali basalt. It is transparent to opaque, with a vitreous lustre. It has relatively high RIs (nα = 1.680-1.685 and nγ = 1.702-1.715) and relatively low birefringence (0.022-0.035), as well as elevated SG values (3.39-3.55). Inclusions consist of distinctive curly fibres of serpentine, and a hazy appearance of some stones is caused by amphibole particles. Raman and FTIR spectroscopy show features characteristic of olivine, and both powder X-ray diffraction and EDXRF chemical analysis indicate the olivine is forsterite. Based on geothermometer calculations from trace-element contents, the olivine crystallised from garnet peridotite in the temperature range of approximately 1400-1460°C and a pressure of 50 kbar. Although this brown olivine has limited usefulness as a gem material, its unusual properties and inclusions may draw the attention of gem collectors. [ABSTRACT FROM AUTHOR]

Bohemian garnet is Cr-bearing pyrope from what is today the Czech Republic that possesses a distinctive 'blood-red' colour. The origins of garnet mining in this part of Europe date back to the fifth century ce. The deposits are known in three non-contiguous areas in the Czech Republic (or Czechia): the Central Bohemian Highlands, the Podkrkonoší area and the Kolín region. During the past two decades, one garnet mine (at Vestřev) closed and one new mine (at Dolní Olešnice) opened, both in the Podkrkonoší region. An open-pit mine at Podsedice in the Central Bohemian Highlands is still productive. Considered the Czech national gemstone since the nineteenth century, Bohemian garnet has been used in a wide range of historical and modern jewellery, although it is rare in sizes above 5 mm (even as rough material). The stones show a characteristic inclusion assemblage, and the presence of Cr in this garnet can be detected by photoluminescence or absorption spectroscopy. [ABSTRACT FROM AUTHOR]

The text discusses the formation and characteristics of cleavelandite, a type of albite mineral found in granitic pegmatites. It explains that cleavelandite forms in cavities after the magma solidifies and that the presence of certain minerals and conditions in the pocket environment contribute to its formation. The text also discusses the differences in cleavelandite formation in LCT and NYF pegmatites, which are different types of granitic pegmatites. Dr. Robert F. Martin explores the formation and characteristics of cleavelandite, proposing that it forms through repeated nucleation in a supercritical fluid phase that is supersaturated with albite, with growth surfaces being poisoned by a nanolayer of phyllosilicate. The presence of cleavelandite in pegmatites indicates a shallow depth and the presence of cavities. Dr. Martin's research contributes to a better understanding of the genesis of cleavelandite and the nature of pegmatite formation. [Extracted from the article]

Due to its high energy density and better safety performance, all-solid-state lithium batteries are regarded as important energy storage devices to replace the traditional liquid electrolyte Li-ion batteries. However, the problems of poor wettability of Li metal anode | solid-state electrolyte interface and easy growth of lithium dendrite have not been well solved. Here, we have constructed Fe-doped Li7-3xFexLa3Zr2O12 (Fe-LLZO) and Li6.5La3Zr1.5Ta0.5O12 (LLZTO) garnet-type double-layer solid electrolyte. The high density of Li7-3xFexLa3Zr2O12 electrolyte and its interfacial wettability to Li metal not only effectively reduced the interface impedance between Li and solid electrolyte but also could stably cycle for more than 200 h without the growth of lithium dendrites at the rate of 0.1 mA cm−2. In addition, the all-solid-state lithium battery (Li|Fe0.1-LLZO|LLZTO|LFP) with LiFePO4 as a cathode also showed excellent cycle stability and C-rate performance. [ABSTRACT FROM AUTHOR]

The St. Leonhard granulite massif in Lower Austria, dominantly formed by kyanite-bearing felsic granulite, encloses countless up to 5 cm sized mantle xenoliths of garnet clinopyroxenite and peridotite. The mineralogical, textural and chemical consequences of a mutual metasomatic interaction at the contact between these xenoliths and the host orthopyroxene-bearing felsic granulite are described. Movement of Mg, Al and, especially, Ca from the garnet clinopyroxenite to the granulite and migration of K and Na in the opposite direction, caused the breakdown of clinopyroxene and formation of orthopyroxene–plagioclase symplectite coronae at the expense of the garnet clinopyroxenite xenoliths. Around the peridotite xenoliths, monomineralic orthopyroxene coronae have developed due to the supply of Si from the host granulite. The P–T conditions of this interaction were established to 900°C to 1000°C and 1.0 to 1.2 GPa by thermodynamic modelling. The duration of coronae growth was constrained to 13 to 532 ka based on modelling of Fe–Mg interdiffusion underlying secondary compositional zoning of garnet from the garnet clinopyroxenite xenolith extending to the coronae. The most significant change in the host granulite was caused by the supply of Ca from the garnet clinopyroxenite xenolith, which led to the breakdown of the Al2SiO5 phase—probably kyanite—and stabilization of orthopyroxene. K-feldspar-poor haloes surrounding mantle xenoliths formed due to the depletion of K in the granulite adjacent to the garnet clinopyroxenite. The observed origin of felsic–intermediate orthopyroxene-bearing granulite by transformation of felsic kyanite-bearing granulite through the metasomatic interaction with mantle xenoliths implies that the deep crustal chemical exchange between mantle- and crust-derived lithologies may have an important consequences on composition, thermal structure and geodynamic evolution of orogenic lower crust especially in hot collisional orogens, such as the European Variscides. [ABSTRACT FROM AUTHOR]

Archean cratons are dominated by tonalite–trondhjemite–granodiorite (TTG) suites, the products of crustal differentiation that formed early continental crust. These rocks may have been primarily generated by partial melting of hydrated basaltic crust in a variety of settings including subduction zones or the deep lithosphere. Sources are mainly inferred from examination of TTGs alone, as potential source rocks are rarely exposed. In the southern Superior Province, Canada, the Kapuskasing Uplift exposes an important crustal cross-section with upper- to middle-crustal TTGs and lower-crustal metabasites, which show evidence of having produced trondhjemitic anatectic melt. Here, we test the hypothesis that these metabasites were the source of the Mesoarchean to Neoarchean TTGs in the Kapuskasing Uplift by combining phase equilibrium and melt trace element modelling with whole-rock and zircon Lu–Hf isotope analysis and geochronology (garnet Lu–Hf and zircon U–Pb) of metabasic samples. By comparison of the results with existing data from TTGs in the Kapuskasing Uplift, we determined that the metabasites are plausible source rocks for the TTGs. The Lu–Hf systematics of the metabasites and TTGs are the most robust evidence of a genetic connection. Modelling results support an increase in TTG source depth over time. New geochronological data constrain partial melting of metabasite and crystallization of anatectic melt between ca. 2685 Ma and ca. 2600 Ma, coeval with crystallization of only the youngest TTGs. Overall, these results indicate a complex history of intracrustal differentiation in the Kapuskasing Uplift, with partial melting of two isotopically distinct lower-crustal metabasic sources at different times and depths. [ABSTRACT FROM AUTHOR]

A model for the refractive index dispersion of garnets was developed by extension of a model for garnet refractive indices at 589 nm wavelength. The cation and anion polarizabilities in garnets were determined as a function of wavelength from dispersion data, and fit to Sellmeier relations. Dispersion predictions were compared to measurements of refractive index between 400 and 5500 nm for 35 garnet compositions. The median prediction error was 0.5% with a maximum error < 4.4%. Sources of error and applications of the predictive method are discussed. [ABSTRACT FROM AUTHOR]

Metamorphic investigations were conducted using mineral chemistry, phase equilibria modelling and conventional thermobarometry on four metamorphic country rock samples from the Nova-Bollinger Ni–Cu deposit, Western Australia. New P–T constraints obtained from phase equilibria modelling of garnet-bearing granulites and cordierite–sillimanite-bearing metasedimentary rocks indicate that the Nova-Bollinger deposit formed at mid-crustal depths (0.75–0.76 GPa and 880–920 °C), along high thermal gradients around 1200 °C/GPa. Peak metamorphic conditions are consistent with those obtained from the Nova-Bollinger intrusive rocks, and with metagabbros from the southern Fraser Zone, but are slightly elevated relative to metapelites examined in the southern Fraser Zone. The peak metamorphic conditions at Nova-Bollinger reflect the combined effects of regional-scale high-T conditions during orogenesis superimposed by contact metamorphism in a thermal aureole adjacent to the Nova-Bollinger mafic–ultramafic magmas. Thermal metamorphism may have been further enhanced by local heat transfer from intruding sulfide liquid, which pervasively infiltrated country rocks on scales of tens to hundreds of metres beneath the orebodies. This additional heat source may be locally significant, despite being volumetrically limited. Retrograde P–T conditions were determined by garnet–biotite conventional thermobarometry of garnet-core–matrix biotite pairs (0.29–0.45 GPa and 550–640 °C). These P–T conditions suggest that the Nova-Bollinger country rocks cooled along a near-isobaric cooling path and reflect the effects of thermal decay following emplacement of voluminous magmas into the Fraser Zone during Stage I Albany–Fraser Orogeny. We present the first quantitative P–T constraints for host rocks of the intrusion-hosted Nova-Bollinger Ni–Cu deposit in the Fraser Zone, Western Australia. Peak metamorphism at Nova-Bollinger occurred at 0.75–0.76 GPa and 880–920 °C (1200 °C/GPa). GBAQ-GB thermobarometry records re-equilibration conditions at 0.29–0.45 GPa and 550–640 °C, indicating near-isobaric retrograde cooling. Infiltration of sulfide liquids into host country rocks may provide a volumetrically low but significant contribution of heat to high-T metamorphism during formation of orthomagmatic deposits in mid-crustal terranes. [ABSTRACT FROM AUTHOR]

This study investigates the uncommon formation of laterite from garnet–sillimanite–gneiss (grt-sil-gn) in the Matale area, a hilly region of Sri Lanka. Geographically, laterites typically form in lowland wet zone of the country, but this research explores their genesis in a unique, less-studied hilly environment. Employing a comprehensive approach combining field observations, petrographic studies, and chemical mapping, we elucidate the contrasting mechanisms of lateritization on the dip slope and scarp slope of a cuesta landform. Our findings reveal a significant influence of weathering conditions and supergene processes on laterite formation. Dip slopes experience intense supergene activity due to deeper groundwater, promoting downward fluid flow and mineral dissolution. Conversely, scarp slopes exhibit isovolumetric leaching with reduced infiltration and enhanced fluid interaction, leading to lateritization along fractures in partially weathered grt-sil-gn. Intense supergene processes on the dip slopes involve downward fluid migration and mineral dissolution, aided by a deep groundwater table. In contrast, scarp slopes exhibit laterite formation through isovolumetric leaching in areas with reduced water infiltration and heightened fluid interaction. Evidence of lateritization includes the formation of gibbsite, hematite, or goethite, attributed to fluctuating oxic and anoxic conditions caused by fluid variations. Additionally, kaolinite patches emerged on the exterior of fully altered garnet, resulting from the weathering products and leachates of quartz, sillimanite, and feldspar. This research emphasizes the critical role of external factors, such as weathering and supergene processes, alongside parent rock composition, in influencing laterite formation. It significantly advances our understanding of lateritization in grt-sil-gn, particularly in hilly areas with lower rainfall compared to usual laterite formation zones. [ABSTRACT FROM AUTHOR]

Thermodynamic modeling has been applied to determine pressure–temperature–time conditions leading to shock vein formation during the passage of a natural shock wave generated by hypervelocity impact. The approach is novel in considering both shock front and rarefaction pressures, as well as simultaneously forming and cooling the shock veins via two‐dimensional steady‐state conduction. Model results are tested using shock veins developed in granitic rocks that constitute the central uplift of the Steen River impact structure in Canada. Here, two variants of majoritic garnet were generated in different settings: (1) along the margins of shock veins due to pargasite and biotite breakdown (accompanied by maskelynite formation), and (2) within the originally molten shock vein matrix as newly grown crystals. We determine that during shock vein formation, the shock front pressure and wave width at the reconstructed sample location were 18 GPa and 830 m, respectively, with a dwell time of 160 ms. Intra‐vein melting at 2150°C was attained within 1 μs. Melt cooled to the solidus in 150 ms following shock front passage. Majoritic garnet formation was facilitated by the high temperatures realized within the veins as a result of frictional melting that accompanied shock loading. The calculated pressure–temperature–time (P–T–t) path provides constraints on the formation conditions of majoritic garnet at Steen River. The model results independently support previously determined P–T conditions based on mineral stability fields. The vein margin garnets (35–39 mole% majorite) and maskelynite formed first under higher P–T conditions for a longer duration (36 ms). The matrix garnets (11–22 mole% majorite) crystallized from melt under lower P–T conditions and for a shorter duration (22 ms). Our results indicate that shock pressure alone should not be used as a basis for shock classification. Instead, the interplay between pressure and temperature with time and the duration of shock immersion (dwell) must be considered. [ABSTRACT FROM AUTHOR]

Cr3+-doped phosphors show great application prospects in near-infrared (NIR) LEDs owing to good compatibility with blue LED chips. However, current NIR phosphors still have some shortcomings in the practical application, such as narrowband emissions and low efficiency. Herein, a new Cr3+-doped Mg 3 Lu 2 Ge 3 O 12 (MLGO) broadband NIR phosphor has been successfully synthesized. X-ray diffraction and transmission electron microscopy demonstrate the sample crystallizes in the garnet structure with the Ia 3 ‾ d space group. Under 442 nm excitation, MLGO:0.04Cr3+ represents a broadband emission centered at 770 nm with a full width at half maximum of 158 nm, and has an external quantum efficiency of 12.5 %. Moreover, the emission intensity of MLGO:0.04Cr3+ at 125 °C still reaches 50 % of that at room temperature. Additionally, a NIR LED device is fabricated by combining the sample with a blue LED chip, and has an excellent NIR output efficiency of 13.1 %. Under the illumination of the NIR LED, clear images can be successfully captured in the dark. Therefore, the MLGO:Cr3+ phosphors can be used for NIR light sources applied in the areas of food analysis and night vision imaging. [ABSTRACT FROM AUTHOR]

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This study tests experimentally the hypothesis that calculated bulk compositions of multiphase solid inclusions present in minerals of ultrahigh pressure rocks, can be equated to the composition of the former trapped fluids. We investigated samples from the ultrahigh pressure garnet peridotites of the Bohemian Massif, spatially associated with ultrahigh pressure crustal rocks and representing a former subduction interface environment. Inclusions present in garnets, composed of amphibole + Ba-mica kinoshitalite + carbonates (dolomite + magnesite + norsethite), were taken to their entrapment conditions of c. 4.5 GPa and 1075 ºC. They (re)crystallized into a garnet fringe at the boundary between inclusion and host garnet, kinoshitalite ± olivine, carbonatite melt, and a hydrous fluid. Although the latter may have exsolved from the carbonatite melt upon quenching, microstructures suggest it was present at trapped conditions, and mass balance indicates that it corresponds to a Na-K-Cl-F-rich saline aqueous fluid (brine). Experiments demonstrate the stability of kinoshitalite at 4.5 GPa and 1075 ºC, and suggest that Ba-rich mica + carbonatite melt + brine coexisted at near-peak conditions. Barium is compatible in the carbonatite melt and mica with respect to the brine, with a partition coefficient between carbonatite melt and mica of ≈ 2.5–3. The garnet fringe formed from incongruent reaction of the former inclusion assemblage due to reversing the fluid(s)-host garnet reaction that occurred upon natural cooling/decompression. Loss of H2 or H2O from the inclusions due to volume diffusion through garnet and/or decrepitation, during geological timeframes upon decompression/cooling, may have prevented rehomogenization to a single homogeneous fluid. Our study shows that great care is needed in the interpretation of multiphase solid inclusions present in ultrahigh pressure rocks. [ABSTRACT FROM AUTHOR]

Rutile inclusions in almandine-spessartine garnet from a peraluminous pegmatoid from the Moldanubian zone (Bohemian Massif, AT) show distinct changes in aspect ratio, shape preferred orientations (SPO) and crystallographic orientation relationships (COR) along the transition between microstructurally different growth zones in the garnet core and rim. For identification of the COR characteristics we pool specific CORs based on their common axial relationship into three COR groups: Group 103R/111G, Group 001R/111G and Group 001R/100G. The rutile inclusions in the garnet core domains are elongated along the four Grt ⟨ 111 ⟩ directions and are dominated by COR Group 103R/111G. The garnet rim zone additionally contains rutile needles elongated along Grt ⟨ 100 ⟩ . Here, Group 001R/111G and 001R/100G are more abundant than in the garnet core. Needle-shaped rutile in the rim shows a systematic correlation between SPOs and CORs as needles elongated parallel to Grt ⟨ 111 ⟩ are dominated by Group 103R/111G and 001R/111G, whereas those needles elongated parallel to Grt ⟨ 100 ⟩ exclusively pertain to CORs of 001R/100G. Furthermore, the frequency of each particular SPO in the garnet rim clearly depends on the local growth direction of the particular Grt{112} sector. Facet-specific variations in rutile SPO frequencies in different sectors and growth zones of garnet were observed even between equivalent directions, indicating that the microstructures and textures of rutile inclusions reflect varying parameters of garnet growth. The characteristic differences in COR groups of different garnet growth zones are referred to compositional changes in the bulk melt or compositional boundary layer, associated with magmatic fractional crystallisation. [ABSTRACT FROM AUTHOR]

We report on the use of an atmospheric pressure, open-air plasma treatment to remove Li2CO3 species from the surface of garnet-type tantalum-doped lithium lanthanum zirconium oxide (Li6.4La3Zr1.4Ta0.6O12, LLZTO) solid-state electrolyte pellets. The Li2CO3 layer, which we show forms on the surface of garnets within 3 min of exposure to ambient moisture and CO2, increases the interface (surface) resistance of LLZTO. The plasma treatment is carried out entirely in ambient and is enabled by use of a custom-built metal shroud that is placed around the plasma nozzle to prevent moisture and CO2 from reacting with the sample. After the plasma treatment, N2 compressed gas is flowed through the shroud to cool the sample and prevent atmospheric species from reacting with the LLZTO. We demonstrate that this approach is effective for removing the Li2CO3 from the surface of LLZTO. The surface chemistry is characterized with X-ray photoelectron spectroscopy to evaluate the effect of process parameters (plasma exposure time and shroud gas chemistry) on removal of the surface species. We also show that the open-air plasma treatment can significantly reduce the interface resistance. This platform demonstrates a path towards open-air processed solid-state batteries. [ABSTRACT FROM AUTHOR]

Solid-state lithium metal batteries are one of the most promising options for next-generation batteries pursuing high-energy density and high-safety. However, the inevitable volatilization of lithium compounds during sintering leads to low relative density and low ionic conductivity of solid-state electrolytes. Herein, the dynamic lithium-compensation mechanism is proposed to facilitate the densification of Ta-substituted garnet-type electrolyte (Li6.5La3Zr1.5Ta0.5O12 (LLZT)) through the reversible manipulating of Li2O atmosphere. Li2ZrO3 is used as mother powder additive, which reacts with Li2O in sintering atmosphere and forms Li6Zr2O7. Li2ZrO3/Li6Zr2O7 buffer pair manipulates the sintering Li2O atmosphere, which is vital for LLZT, within the Li2O partial pressure range corresponding to Li2ZrO3 and Li6Zr2O7. Furthermore, the reversibility mechanism of buffer pair for Li2O absorption and release is revealed. The obtained LLZT exhibits a relative density of over 96% and an ionic conductivity exceeding 7 × 10−4 S·cm−1 with no abnormal grain growth. The symmetric cell demonstrates an excellent lithium dendrite suppressing ability (stable cycling at a current density of 0.3 mA·cm−2 for over 1000 h). Such dynamic lithium-compensation strategy has been successfully applied in atmosphere manipulation of LLZT sintering process, which reduces the dependence of LLZT on the Li2O atmosphere, making it conducive to large-scale preparation of electrolyte ceramics. [ABSTRACT FROM AUTHOR]

A model for the refractive index dispersion of garnets was developed by extension of a model for garnet refractive indices at 589 nm wavelength. The cation and anion polarizabilities in garnets were determined as a function of wavelength from dispersion data, and fit to Sellmeier relations. Dispersion predictions were compared to measurements of refractive index between 400 and 5500 nm for 35 garnet compositions. The median prediction error was 0.5% with a maximum error < 4.4%. Sources of error and applications of the predictive method are discussed. [ABSTRACT FROM AUTHOR]

Garnet oxide is one of the most promising solid electrolytes for solid-state lithium metal batteries. However, the traditional interface modification layers cannot completely block electron migrating from the current collector to the interior of the solid-state electrolyte, which promotes the penetration of lithium dendrites. In this work, a highly electron-blocking interlayer composed of potassium fluoride (KF) is deposited on garnet oxide Li6.4La3Zr1.4Ta0.6O12 (LLZTO). After reacting with melted lithium metal, KF in-situ transforms to KF/LiF interlayer, which can block the electron leakage and inhibit lithium dendrite growth. The Li symmetric cells using the interlayer show a long cycle life of ~3000 hours at 0.2 mA cm−2 and over 350 hours at 0.5 mA cm−2 respectively. Moreover, an ionic liquid of LiTFSI in C4mim-TFSI is screened to wet the LLZTO|LiNi0.8Co0.1Mn0.1O2 (NCM) positive electrode interfaces. The Li|KF-LLZTO | NCM cells present a specific capacity of 109.3 mAh g−1, long lifespan of 3500 cycles and capacity retention of 72.5% at 25 °C and 2 C (380 mA g−1) with an average coulombic efficiency of 99.99%. This work provides a simple and integrated strategy on high-performance quasi-solid-state lithium metal batteries. Formation of dendrites in solid-state lithium batteries hampers their application. Here, authors deposit a thin film of potassium fluoride on a garnet solid electrolyte that in-situ transforms to a mixed fluoride layer, which blocks electron leakage and inhibits lithium dendrite growth. [ABSTRACT FROM AUTHOR]

Garnet-type solid electrolytes stand out as promising Li-ion conductors for the next-generation batteries. It has been demonstrated that the inherent properties of garnets can be tailored by introducing various dopants into their crystal structures. Recently, there has been a growing interest in the concept of high entropy stabilization for materials design. In this study, we synthesized high-entropy garnets denoted as Li6La3Zro.7Tio.3Tao.5Sbo.5Oi2 (LLZTTSO), wherein Ti, Sb, and Ta occupy the Zr site. The formation of the cubic garnet phase in LLZTTSO was confirmed through X-ray diffraction (XRD), and the resulting lattice parameter agreed with predictions made using computational methods. Despite the substantial porosity (relative density 80.6%) attributed to the low sintering temperature, LLZTTSO exhibits a bulk ionic conductivity of 0.099 mS cm-1 at 25°C, and a total ionic conductivity of 0.088 mS cm-1, accompanied by an activation energy of 0.497 eV. Furthermore, LLZTTSO demonstrates a critical current density of 0.275mAcm-2 at 25°C, showcasing its potential even without any interfacial modification. [ABSTRACT FROM AUTHOR]

Ecological restoration of bauxite residue has received extensive attention, and organic matter plays a crucial role in the soil formation process of bauxite residue. However, the interaction between organic matter and alkaline minerals in bauxite residue is not well understood. In this work, molecular spectroscopic techniques combined with isothermal titration calorimetry (ITC) were employed to investigate the interactions between humic acid (HA) and four representative alkaline minerals in bauxite residue (calcite, garnet, sodalite, and cancrinite). The results show that the adsorption processes of HA onto calcite and garnet were primarily governed by monolayer surface adsorption and controlled by surface reactions, which were different for sodalite and cancrinite. Both garnet and cancrinite had strong binding affinities with fluorescent HA, while cancrinite only bound with a small fraction of HA. In contrast, the bindings of calcite and sodalite with fluorescent HA were weak. The ITC results indicate distinct thermodynamic properties of different alkaline minerals in the interaction with HA. The molar enthalpy of calcite was − 45.88 kJ/mol, which was much higher than those of garnet, sodalite, and cancrinite, suggesting that calcite exhibited a relatively uniform interaction mechanism with HA dominated by enthalpy change, while the others showed heterogeneous entropy-driven mechanisms. The findings contribute to a better understanding on the microscale connections between organic matter and alkaline minerals in bauxite residue. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. It includes a list of papers featured in the issue, covering topics such as photoluminescent detection, phosphors for light-emitting diodes, crystal derivatives, piezoelectric materials, graphene growth, and nanocrystal synthesis. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document also mentions approved training courses offered by the society. [Extracted from the article]

Exploring efficient, energy-saving and environmentally friendly phosphors is important for developing solid-state white light-emitting diodes (w-LEDs). Herein, we report a novel highly efficient green-emitting Ce3+-activated Ca2LuScAl2Si2O12 (abbreviated as CLSAS:Ce3+) garnet phosphor with high quantum efficiency and good thermal stability. These garnet phosphor samples doped with different Ce3+ ion concentrations were synthesized using a high-temperature solid-state method. The crystal structure and Ce3+ concentration-dependent luminescence properties of the phosphors were systematically studied. The as-prepared CLSAS:Ce3+ garnet phosphors exhibit broadband absorption in the spectral range of 250–510 nm with a maximum excitation wavelength of around 452 nm, matching well with the emission wavelengths of commercial blue LED chips. Under an excitation of 452 nm, the optimal CLSAS:4%Ce3+ sample exhibited a broad green emission band (emission peak: 531 nm; bandwidth: 114 nm) with CIE color coordinates of (0.3293, 0.5453) and high luminescence efficiency (internal quantum efficiency: 87.3%; external quantum efficiency: 56.6%). The CLSAS:4%Ce3+ sample also showed good thermal stability in the temperature range of 303–443 K. Its emission intensity at 423 K reached 79% of the emission intensity at 303 K, and it exhibited outstanding color stability with a small color chromaticity shift (ΔE = 1.07 × 10−3) at 423 K. Importantly, the fabricated w-LED device exhibits excellent photoelectric properties (CCT = 4978 K; Ra = 92.4; LE = 69.59 lm W−1). The obtained efficient CLSAS:Ce3+ green phosphors have the potential for application in high-quality w-LEDs. [ABSTRACT FROM AUTHOR]

A series of high-pressure multi-anvil experiments were conducted in the MgO-Al 2 O 3 system between 15 and 50 GPa and at temperatures up to 2623 K, to determine the solubility of Al 2 O 3 in periclase in the stability fields of coexisting spinel, corundum, the Mg 2 Al 2 O 5 modified ludwigite phase, the MgAl 2 O 4 calcium ferrite phase, and the MgAl 2 O 4 calcium titanate phase. The Al 2 O 3 solubility in periclase is strongly temperature-dependent over the conditions investigated. Conversely, periclase Al 2 O 3 solubility exhibits a negative relationship with pressure. Experiments with up to 40 mol.% FeO in ferropericlase show Al 2 O 3 solubilities that are near identical to those of periclase, within experimental uncertainties. A simple thermodynamic model incorporating significant literature on ambient pressure measurements is able to describe periclase Al 2 O 3 solubility up to 40 GPa. This model is used to investigate the Al 2 O 3 contents of ferropericlase inclusions observed in natural diamonds, which vary up to 0.35 mol. %. Pressure–temperature curves along which particular inclusions formed can be produced if equilibrium can be assumed with Al-bearing minerals found in the same diamond. Alternatively, the maximum possible Al 2 O 3 content in ferropericlase can be determined for a certain pressure–temperature profile and inclusions with Al 2 O 3 contents that exceed this curve can be excluded from those conditions. To obtain such solubility curves, calculations are performed for periclase coexisting with the Al-rich phases spinel, garnet, bridgmanite and the MgAl 2 O 4 calcium ferrite phase. The calculations indicate that periclase, and by inference ferropericlase, Al 2 O 3 -contents cannot be greater than 0.5 mol.% under present day adiabatic mantle temperatures and go through a minimum at mantle transition zone conditions. This excludes a number of Al-rich ferropericlase inclusions found in natural diamonds from being formed in the transition zone, unless temperatures were super-adiabatic. This subset of inclusions likely formed either at the base of the upper mantle or the top of the lower mantle, but must have formed at near adiabatic temperatures. The majority of ferropericlase inclusions have Al 2 O 3 contents that would be consistent with formation in the transition zone at near slab temperatures, but could still have been formed at higher temperatures if Al 2 O 3 activities were low. [ABSTRACT FROM AUTHOR]

Composite solid electrolytes (CSEs) integrate the fast ion conductivity of inorganic electrolytes and the excellent interfacial compatibility of polymer electrolytes. Typically, fluoropolymers and garnets are promising individuals to formulate cutting‐edge CSEs owing to their unique properties. However, the alkaline garnets can induce the dehydrofluorination of fluoropolymers, deteriorating their CSEs performance. Here, for the first time, NH4HCO3 is proposed as a sacrificial inhibitor to effectively prevent the garnet‐induced dehydrofluorination, using Li6.4La3Zr1.4Ta0.6O12 (LLZTO) and poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVH) as symbolic garnets and fluoropolymers, respectively. Various findings demonstrate that NH4HCO3 can buffer the alkalinity of LLZTO, thereby inhibiting the dehydrofluorination of PVH. In addition, NH4HCO3 can completely decompose to volatiles upon drying without compromising the properties of LLZTO and PVH. Additionally, a polymer‐in‐salt strategy is further introduced by adding high‐concentration LiTFSI salt to the above system, resulting in the PVH/LiTFSI/LLZTO (PLL) CSEs. Benefiting from the synergetic coupling of the sacrificial inhibitor and polymer‐in‐salt strategies, the PLL exhibits an exceptionally high ionic conductivity of 1.2 mS cm−1 at 25 °C and stable voltage of 5.09 V, outperforming other reported CSEs. Consequently, the PLL delivers impressive high‐rate cyclability in solid‐state lithium‐metal batteries with an outstanding capacity retention of 95.4% after 240 cycles at 1 C (25 °C). [ABSTRACT FROM AUTHOR]

This study explores multi-component garnet-based materials as solid electrolytes for all-solid-state lithium batteries. Through a combination of computational and experimental approaches, we investigate the thermodynamic and structural properties of lithium lanthanum zirconium oxide garnets doped with various elements. Applying density functional theory, the influence of dopants on the thermodynamic stability of these garnets was studied. Probable atomic configurations and their impact on materials' properties were investigated with the focus on understanding the influence of these configurations on structural stability, phase preference, and ionic conductivity. In addition to the computational study, series of cubic-phase garnet compounds were synthesized and their electrochemical performance was evaluated experimentally. Our findings reveal that the stability of cubic phase in doped Li-garnets is primarily governed by enthalpy, with configurational entropy playing a secondary role. Moreover, we establish that the increased number of doping elements significantly enhances the cubic phase's stability. This in-depth understanding of materials' properties at atomic level establishes the basis for optimizing high-entropy ceramics, contributing significantly to the advancement of solid-state lithium batteries and other applications requiring innovative material solutions. [ABSTRACT FROM AUTHOR]

Wheat is a major food crop that plays a crucial role in the human diet. Various breeding technologies have been developed and refined to meet the increasing global wheat demand. Several studies have suggested breeding strategies that combine generation acceleration systems and molecular breeding methods to maximize breeding efficiency. However, real-world examples demonstrating the effective utilization of these strategies in breeding programs are lacking. In this study, we designed and demonstrated a synergized breeding strategy (SBS) that combines rapid and efficient breeding techniques, including speed breeding, speed vernalization, phenotypic selection, backcrossing, and marker-assisted selection. These breeding techniques were tailored to the specific characteristics of the breeding materials and objectives. Using the SBS approach, from artificial crossing to the initial observed yield trial under field conditions only took 3.5 years, resulting in a 53% reduction in the time required to develop a BC2 nearisogenic line (NIL) and achieving a higher recurrent genome recovery of 91.5% compared to traditional field conditions. We developed a new wheat NIL derived from cv. Jokyoung, a leading cultivar in Korea. Milyang56 exhibited improved protein content, sodium dodecyl sulfate-sedimentation value, and loaf volume compared to Jokyoung, which were attributed to introgression of the Glu-B1i allele from the donor parent, cv. Garnet. SBS represents a flexible breeding model that can be applied by breeders for developing breeding materials and mapping populations, as well as analyzing the environmental effects of specific genes or loci and for trait stacking. [ABSTRACT FROM AUTHOR]

Ytterbium monosilicate (Yb 2 SiO 5) has been recognized as environmental barrier coatings (EBCs) material with potential applications for SiC f /SiC. However, the corrosion caused by calcium-magnesium-alumino-silicate (CMAS) has posed significant challenges to the design and application of EBCs. In this study, reaction of Yb 2 SiO 5 EBCs against CMAS melts with different Ca/Si ratios (1.1, 0.75, 0.64, and 0.42) at 1350 °C was investigated. Results showed that the components of CMAS have a significant impact on the corrosion behaviors of the Yb 2 SiO 5 coating. The difference in Ca/Si ratio of CMAS changes the phase equilibrium during the reaction process. The CMAS melts with the highest Ca/Si ratios can form a combination of silico-carnotite (Ca 3 Yb 2 (SiO 4) 3), garnet and two kinds of apatite (Ca 2 Yb 8 (SiO 4) 6 O 2 and Ca 4 Yb 6 (SiO 4) 6 O), whereas the CMAS melts with the lowest Ca/Si ratio is expected to form Yb 2 Si 2 O 7 phase. With the Ca/Si ratio increasing, the viscosity of CMAS decreased and the aggressiveness of CMAS to Yb 2 SiO 5 coating increased. [ABSTRACT FROM AUTHOR]

Skarn and Fe-Zn-Pb mineralization at the Wondong deposit located in the Taebaeksan Basin of the central-eastern region of Korean Peninsula occurs along the contact between the Upper Cretaceous quartz-feldspar porphyry (QFP) and carbonate rocks of the Ordovician Makgol Formation. The QFP is relatively fresh and has a sharp contact with the garnet skarn. Skarn is dominant in the carbonate rocks but is rare in the QFP. It consists almost of grandite throughout the skarn but has mineralogical zonation of proximal garnet, intermediate pyroxene, and distal wollastonite with increasing distance from the contact between the QFP and garnet skarn. Garnet becomes Fe-rich, and pyroxene tends to be enriched in Fe and Mn toward the marble front. Massive Fe mineralization, replacing garnet skarn, is restricted proximal to the QFP. In contrast, although the Zn-Pb mineralization is found in all areas it mostly occurs in the carbonate rocks beyond the skarn. Zinc-Pb mineralization occurred as stockwork and vein in the QFP and the garnet skarn consists of sphalerite, galena, Al-rich garnet, and calcite with a minor quantity of arsenopyrite. In contrast, the carbonate replacement of the Zn-Pb mineralization beyond skarn consists of sphalerite, pyrrhotite, galena, diopsidic pyroxene, and calcite with minor minerals such as arsenopyrite, löellingite, and chalcopyrite. Sphalerite, principal ore mineral, becomes darker and Fe- (up to 34.4 mol% FeS) and Mn-rich (up to 1.5 mol% MnS) with increasing distance from the QFP. Arsenopyrite is closely associated with sphalerite tends to be decreased in As away from the QFP. All sulfide minerals from Zn-Pb mineralization in the Wondong deposit have δ34S values ranging from 2.9 to 5.9‰, which are attributed to the magmatic source. In addition, the narrow range and subtle variation of the δ34S values for all sulfides throughout the Wondong deposits are not interpreted to be involved in the mixing of multiple sulfur sources. Geological, petrographic, mineralogical, and isotopic geochemical investigations show that the early skarn was formed in an environment of high fluid: rock ratios at the contact between the QFP and Makgol Formation and it was dominated by grandite, indicating the oxidizing nature of the skarn-forming fluids. The ore deposition began after the formation of the main garnet dominated skarn. The ore-forming fluids responsible for Zn-Pb mineralization are characterized by a less oxidizing nature, as defined by comparatively Al-enriched garnet in vein type mineralization in and around the QFP. Farther, the fluids producing the carbonate replacement of the Zn-Pb mineralization are unlikely to be engaged in external effects such as mixing with multiple sulfur sources even though it travels over long distance. [ABSTRACT FROM AUTHOR]

Aluminum garnets display exceptional adaptability in incorporating mismatching elements, thereby facilitating the synthesis of novel materials with tailored properties. This study explored Ce3+-doped Tb3Al5−xScxO12 crystals (where x ranges from 0.5 to 3.0), revealing a novel approach to control luminescence and photoconversion through atomic size mismatch engineering. Raman spectroscopy confirmed the coexistence of garnet and perovskite phases, with Sc substitution significantly influencing the garnet lattice and induced A1g mode softening up to Sc concentration x = 2.0. The Sc atoms controlled sub-eutectic inclusion formation, creating efficient light scattering centers and unveiling a compositional threshold for octahedral site saturation. This modulation enabled the control of energy transfer dynamics between Ce3+ and Tb3+ ions, enhancing luminescence and mitigating quenching. The Sc admixing process regulated luminous efficacy (LE), color rendering index (CRI), and correlated color temperature (CCT), with adjustments in CRI from 68 to 84 and CCT from 3545 K to 12,958 K. The Ce3+-doped Tb3Al5−xScxO12 crystal (where x = 2.0) achieved the highest LE of 114.6 lm/W and emitted light at a CCT of 4942 K, similar to daylight white. This approach enables the design and development of functional materials with tailored optical properties applicable to lighting technology, persistent phosphors, scintillators, and storage phosphors. [ABSTRACT FROM AUTHOR]

Estimates of oxygen fugacity of eclogitic rocks are linked to the redox evolution of the oceanic protolith during subduction and its residence in the lithospheric mantle, and, based on knowledge of pressures and temperatures, allow modelling of the speciation of volatile elements and diamond (or graphite) versus carbonate stability. To date, the oxygen fugacity of mantle eclogites has been shown to vary between −6 (Kasai, Congo and Udachnaya, Siberia) and −0.1 (Udachnaya, Siberia) log units (relative to the fayalite–magnetite–quartz buffer, FMQ), linked to the low Fe3+ contents of garnets. In this study, we investigated the Fe oxidation state of coexisting garnet and clinopyroxene hand-picked out of 17 diamond-free high-MgO and low-MgO mantle eclogites (dated at 2.84 Ga) from the Grib kimberlite pipe (East-European platform). Measured Fe3+/∑Fe values range between 0.03 and 0.19 for garnet and 0.18–0.38 for clinopyroxene, the former being higher than what was measured previously in garnets equilibrated at mantle conditions. The Fe3+/∑Fe of the reconstructed bulk rock ranges between 0.10 and 0.15 for high-MgO eclogites and 0.10 and 0.24 for low-MgO eclogites (with uncertainties of ± 0.02 and ± 0.03 in both cases). Thermobarometric calculations result in equilibration pressures and temperatures of 3.0–5.2 (± 0.4) GPa and 720–1050 (± 60) °C for both high-MgO and low-MgO eclogites, slightly lower than previous P–T estimates of mantle eclogites from the Udachnaya kimberlite pipe (Siberian craton). At these conditions, ∆log f o2 (FMQ) calculated using the available oxythermobarometric model varies from −1.7 to −0.6 log units for high-MgO eclogites and from −2.9 to 0.9 log units for low-MgO eclogites. Samples recording ∆log f o2 (FMQ) ≤ −1 log units overlap with North Slave, West Africa and Udachnaya eclogites, with no difference among eclogite types. The average values of −1.2 (± 0.4) log units for high-MgO and −0.6 (± 1.1) log units for low-MgO eclogites suggest different redox conditions of basaltic protoliths during subduction worldwide. Previous geochemical studies on the same rock samples reported evidence of cryptic metasomatism in both garnet and clinopyroxene that we demonstrate being not recorded by their major elements, while modal metasomatism evidenced by the presence of phlogopite as a product of interaction with a kimberlitic melt only affects the MgO of the bulk rock. Therefore, we suggest that high Fe3+/∑Fe ratios for garnet (> 0.10) and for reconstructed bulk rocks in the case of both low-MgO and high-MgO samples cannot be due to metasomatic interaction with an oxidized fluid, but rather are the consequence of Fe3+ redistribution in an unusually oxidized mafic protolith upon metamorphism. Our results highlight the redox variability of eclogites of Archaean age at conditions more oxidized than present-day mid-ocean ridge basalts (MORBs) and imply an oxidizing nature of the convective mantle source where magma was formed with consequent speciation of C in the form of carbonate fluid explaining, therefore, the lack of eclogitic diamonds in V. Grib kimberlite pipe. [ABSTRACT FROM AUTHOR]

The investigation of multifunctional bright materials is a popular research topic. The first report of the Bi3+, Tb3+, and Eu3+ triple‐doped garnet‐derived structure Lu2Mg2Al2Si2O12 phosphor is presented in this study. The energy transfer system was constructed with unique ultraviolet (UV) emission of Bi3+ ions, which allows phosphor to be used for temperature sensing with self‐calibration capability, Sa = 0.26% (148 K) and 0.56% (98 K), Sr = 0.15% (98 K), and 0.21% (148 K), indicating a high sensitivity in the low‐temperature region. Tb3+ and Eu3+ ions with better thermal stability under 325 nm excitation were chosen to achieve higher pressure sensing performance, the sensitivity was calculated by fluorescence intensity ratio technique and has maximum sensitivities of up to 0.1887 (SPa) and 0.1621 G/Pa (SPr). This provides a new idea for the ensuing design of brand‐new phosphors for optical pressure sensing. This study provides a new perspective on the versatile applications of phosphors. [ABSTRACT FROM AUTHOR]

Transition‐metal Mn2+ ion‐doped transparent ceramics (TCs) are promising color‐convertors to improve color rendition for solid‐state lighting. However, the stabilization of Mn2+ remains a challenge owing to the changeable atmosphere in the specific preparation of TC. In this work, the variations of valence states of Mn ions in typical garnet lattice host (YAG and LuAG) throughout the TC fabrication were demonstrated. By combined first principles calculation and experimental investigation, an enhanced self‐reduction of Mn ions was clarified in LuAG host, which was originated from the higher concentration of oxygen vacancy defects. Moreover, the air annealing treatment could significantly weaken and enhance the absorption of Mn2+ and Mn3+ respectively, degrading the orange–red emission peaking at 594 nm. On account of the oxidation of Mn2+ ions, a photoluminescence spectra redshift of 9 nm was observed with increasing air annealing temperature and oxygen content, owing to strengthened crystal field strength surrounding Mn2+ ions. Finally, a high color rendering index of 74.5 of resultant white laser diodes device structured by single‐phase LuAG:Ce,Mn TCs was obtained based on an efficient energy transfer process from Ce3+ to Mn2+. This study will deepen the understanding of the crystal defects inside TCs on luminescence properties, as well as inspiring more exploration on defect control to develop high performance ceramic color‐convertor. [ABSTRACT FROM AUTHOR]

The article focuses on various intriguing gemological phenomena. Topics include the discovery of a conch shell-like fracture in a diamond, a square-shaped cloud inclusion in a round brilliant diamond, and unique surface etching patterns in beryl samples from China, providing insight into the natural and artistic aspects of gem formation and treatment.

The Fe skarn and vein-type Cu mineralization types are common in the Eastern Taurus Mountains. This study aims to determine the U-Pb geochronology of garnets of varying sizes within the skarn zone developed at the quartz diorite–marble contact zone in Ayazpınar, Pertek District, Tunceli Province, Turkey. Additionally, this study aims to determine the age of the skarnization and the types of inclusion minerals in the garnets. Faulting and magma emplacement along the thrust plane caused mineralization in the Eastern Taurus Mountains, especially at the marble and quartz diorite contact zone between the cities of Elazığ and Tunceli. The greenish garnets found in the Ayazpınar deposit are characteristic of distal skarns, while red or brown Pertek garnets are observed in the proximal skarns. The garnets typically feature a core–rim texture. The cores of the garnet crystals are large, reddish in color, and have a high REE (Ce, Pr) content. Moreover, the cores have higher Fe and lower Al ratios, alongside higher La, Ce, and Pr contents, than the rims. We propose that the compositional differences between the rims and the cores reflect the transition from oxidized REE- and Fe3+-rich liquids to liquids with lower REE and Fe3+ contents, producing the differences in the garnet colors. Green garnets show lower REE contents than brown garnets with Fe-rich cores. The skarn under study includes the following successively formed zones: diorite → epidote skarn → garnet–magnetite → pyrite–garnet–magnetite → calcite carbonate. Diopside, magnetite, and hematite, including small grains, are surrounded or enveloped by garnets. The U-Pb age of the mineralization is 74.1 ± 5 Ma, indicating that the mineralization occurred concurrently with the intrusion settlement. [ABSTRACT FROM AUTHOR]

Incorporation of rare earth elements (REE) in garnet enables garnet chronology (Sm‐Nd, Lu‐Hf), and imparts a garnet‐stable signature on cogenetic phases, which allows petrochronology and general petrogenetic tracing of garnet stability in minerals and melts. Constraints on the uptake and redistribution mechanisms, as well as on the diffusive behaviour of REE in garnet are required for allowing accurate interpretation of REE signatures and ages. Garnet REE profiles are often measured to gain insight into the nature and cause of REE zoning. Interpretation of such profiles is nevertheless complicated by poor constraints on the extent of diffusive relaxation. This is especially relevant for Lu, which, according to experiments, has a relatively high diffusivity and thus may re‐equilibrate with possible consequences for Lu‐Hf chronology. To provide new insight into the REE systematics of garnet, we applied quantitative trace‐element mapping of garnet grains from metamorphic rocks that record peak temperatures above 750°C and cooling rates as low as 1.5°C Ma−1. Garnet in all samples preserves Rayleigh‐type or oscillatory growth zoning with sharply defined interfacial angles that match the garnet habit. Re‐equilibration of REE compositions appears restricted to domains with nebulous and patchy zoning, which likely form by interface‐coupled dissolution and re‐precipitation reactions mediated by fluids or melts, rather than REE volume diffusion. The possible effect of Lu diffusion in the analysed grains was investigated by comparing the observations to the results from 2D numerical modelling using Lu diffusivities from recent diffusion experiments. This test indicates that Lu diffuses significantly slower in natural garnet than experiments predict. The retentiveness of REE in garnet demonstrates the reliability of REE signatures in magmatic tracing and petrochronology and establishes Lu‐Hf chronology as a robust means of dating garnet growth and recrystallization in metamorphic rocks, including those that underwent high‐ or ultrahigh‐temperature conditions. [ABSTRACT FROM AUTHOR]

Polymetamorphic metapelitic rocks in central‐west Tasmania, southern Australia, contain high‐pressure mineral assemblages that formed during Cambrian‐aged subduction and relict garnet with published Lu–Hf ages of c. 1285–1240 Ma. These garnet ages, along with published detrital zircon data from throughout western Tasmania and western North America, have been used to propose the presence of Mesoproterozoic Laurentian crust in western Tasmania. In this study, we combine zircon petrochronology with compositional information from the inclusion assemblages in relict garnet to extract Mesoproterozoic pressure–temperature data from subduction‐overprinted rocks, which effectively constitute an interpreted remnant of Laurentian crust now residing in central‐west Tasmania. The new data suggest Mesoproterozoic metamorphism involved two stages. The first event is recorded by c. 1480–1235 Ma zircon that formed in a garnet‐absent, plagioclase‐present, high‐thermal gradient environment at pressures no greater than ~5–5.5 kbar. The second event recorded by c. 1285–1240 Ma relict garnet was characterized by the development of a moderate‐pressure kyanite–plagioclase–biotite‐bearing mineral assemblage, which formed at ~8.5 kbar and ~590–680°C. These pressure–temperature constraints are attributed to extension within a deep basin system associated with the cryptic East Kootenay Orogeny in North America, which coincides with the final stages of c. 1450–1370 Ma upper Belt‐Purcell Basin sedimentation. Taking into account new detrital zircon U–Pb–Hf isotopic data from central‐west Tasmania in this study and existing zircon provenance data from throughout western Tasmania and the Belt‐Purcell Basin, our results strengthen the hypothesis of a Laurentian footprint that potentially encompasses much of western Tasmania and relates to both Nuna and Rodinian tectonism. [ABSTRACT FROM AUTHOR]

Aqueous fluids released during dehydration of a subducting slab have a large effect on the rheology of the subduction interface. While high‐pressure experiments and natural‐case studies link deformation with critical dehydration reactions during eclogitization, the exact interplay between these processes remains ambiguous. To investigate fluid–rock interaction and associated deformation at high‐pressure, we studied a suite of eclogites from the Tsäkkok Lens of the Scandinavian Caledonides that record prograde metamorphism within an Early Palaeozoic cold subduction zone. Our results show that in‐situ dehydration during the blueschist to eclogite facies transition produces fluid fluxes leading to rheological weakening and densification, consequently promoting ductile‐brittle deformation. Petrographic evidence, supported by thermodynamic modelling and thermobarometry, attest to a prograde passage from lawsonite‐blueschist to peak eclogite facies of ~2.5 GPa and ~620°C. Phengite‐bearing eclogites imply interaction with an externally‐derived fluid, whereas rare phengite‐free, kyanite‐eclogites only record internally‐derived fluid production. Models predict that prograde breakdown of chlorite, lawsonite and amphibole between 500 and 610°C lead to progressive dehydration and release of up to 4.6 wt.% of aqueous fluid. Microstructural data reveal elongated shapes of highly strained omphacite porphyroblasts, displaying minor yet gradual changes in misorientation towards the grain boundaries. Occasionally, these intragranular structures form subgrain cells that have similar sizes to those of neoblasts in the rock matrix. These observations point to the potential onset of dynamic recrystallization processes via dislocation creep. Moreover, the omphacite neoblasts and rutile show non‐random crystallographic preferred orientations (CPOs), which are characterized by the subparallel alignment of point‐like maxima in rutile [001] and [100] axes to those of [001] and (010) of omphacite neoblasts, respectively. Additionally, the [001] axes of these minerals are also subparallel to the weak stretching mineral lineation, and the (100) of rutile and the (010) of omphacite neoblasts are distributed in the plane of the foliation. This suggests that the development of their CPOs was coeval and structurally controlled. Garnet microfractures normal to the foliation are dilated and sealed predominantly by omphacite. The lack of obliquity between CPO and foliation plane, as well as the systematic orientation of garnet microfracture orientations, are consistent with coaxial deformation at peak‐pressure conditions. Unlike other studies, we show that neither an external fluid source nor channelized fluid flow is needed to facilitate a ductile‐brittle deformation of eclogite in a subduction setting. [ABSTRACT FROM AUTHOR]

Archean to Palaeoproterozoic basement rocks exposed in the Dunhuang block in NW China were affected by Palaeozoic crustal reworking, as constrained by previous zircon U–Pb geochronological investigations. However, relationships between the Palaeozoic metamorphic ages, P–T evolution and deformational history of the region remain ambiguous. In order to address this issue, P–T–t–D paths of paragneisses from the basement of the Hongliuxia belt in the southern Dunhuang block were investigated. Inclusions in garnet and kyanite from the paragneisses are considered as vestiges of Palaeozoic M1 metamorphism corresponding to initiation of the prograde evolution. The earliest continuous metamorphic fabric is an originally steep N–S striking foliation S2. This fabric was reworked by vertical folds F3 associated with the development of a ubiquitous steep, mainly south‐dipping, E‐W striking axial planar foliation S3. The S2 foliation in paragneisses is mainly associated with Grt–St–Ky–Sil–Bt–Ms–Pl–Qz–Rt assemblages in samples from the western domain and with Grt–Ky–Sil–Bt–Kfs–Pl–Qz–Rt assemblages in samples from the northeastern domain of the Hongliuxia belt. The S3 foliation is associated with Grt–Sil–St–Bt–Ms–Pl–Qz–Ilm assemblages in the western domain and with Grt–Sil–Bt–Ms–Pl–Qz–Kfs–Ilm assemblages in the northeastern domain, followed by growth of chlorite in both domains. Early prograde stage (M1) from 4.0–6.5 kbar and 540–560°C to metamorphic peak (M2a) at 9–10 kbar and ~650–675°C is mainly recorded by paragneisses from the western domain. Subsequent decompression is initially accompanied by heating (M2b) constrained to 6.5–7 kbar and 675–710°C in the western domain, and to 6–6.5 kbar and ~730°C in the northeastern domain, followed by cooling (M3) through 4–6.5 kbar and 550–650°C till late chloritization (late M3). In situ U–Pb dating of monazite combined with monazite trace‐element compositions suggests that prograde evolution (M1) most likely started at c. 406 Ma, peak‐P conditions (M2a) were reached at 400–394 Ma, decompression associated with heating (M2b) took place at 393–391 Ma, and cooling (M3) during exhumation probably lasted from 380 to 354 Ma. The prograde metamorphism probably reflects burial during underthrusting of neighbouring continental basement (the Alxa block or an equivalent) below the Dunhuang block. This event culminated in pure shear thickening (D2a) of the whole supra‐subduction margin followed by minor heating and exhumation (D2b). The D3‐M3 event is interpreted as reflecting exhumation during orthogonal shortening of the system, possibly in response to an independent orogenic cycle. Combined with the available regional data, this study reveals the existence of a complex tectono‐metamorphic evolution for the Dunhuang block characterized by two distinct orogenic phases with (i) the thickening of a previously thinned arc‐back‐arc crust recorded in the northern and central belts at 420–410 Ma in the pro‐wedge side of the active margin (Sanweishan phase), followed by (ii) the 410–390 Ma thickening in the retro‐wedge side (Hongliuxia phase). Such a tectonic evolution of the whole Dunhuang block resembles Andean‐type migration of crustal thickening from the convergent front to hinterlands. The D3‐M3 event, potentially responsible for the juxtaposition of rocks from different geological occurrences and depths, is seemingly independent from this Andean‐type orogenic cycle. [ABSTRACT FROM AUTHOR]

The 3D microstructure and compositional zoning of garnet populations in micaschists from the Kolvik and Bekkarfjord nappes indicate the quasi‐equilibration of their major components across the rock matrices during interface‐controlled, size‐independent garnet growth. There is microstructural evidence for foliation‐parallel, small‐scale resorption of garnet rims in the Kolvik Nappe, influencing the metamorphic peak conditions obtained from thermodynamic modelling. The local chemical compositions of rims less affected by resorption indicate a peak temperature of ~630°C, which is ~40°C higher than the temperature obtained from resorbed rims of the largest garnet crystal. Using a diffusion geospeedometry approach that considers the geometry of the compositional zoning of the garnet population, as well as the higher, more realistic peak temperature, a duration of 1 to 4.9 Myr is obtained for garnet growth in the Kolvik Nappe. This is approximately 1 order of magnitude faster than duration estimates obtained when using the apparent, lower temperature estimated from the resorbed garnet rims. Concomitantly to garnet growth in the Kolvik Nappe, garnet overgrowths formed in the Bekkarfjord Nappe for circa 2.5 Myr at metamorphic peak temperatures of ~560°C. The garnet growth durations obtained here are comparable with the uncertainty on the Lu–Hf garnet–whole rock isochron ages of 419.9 ± 2.4 Ma and 423.0 ± 1.9 Ma, previously obtained for these rocks. These results provide new insight into the timescales of repeated Barrovian‐type metamorphic events experienced by the lower nappes of the Kalak Nappe Complex during the Caledonian Orogeny in Arctic Norway. This study emphasizes the importance of microstructural and chemical characterization of garnet populations in assessing metamorphic crystallization mechanisms and the extent of equilibration of garnet‐forming components during prograde metamorphism. Moreover, our results provide means for reducing the uncertainty on metamorphic durations obtained via diffusion geospeedometry and, so, contributing to our understanding of geological timescales and processes. [ABSTRACT FROM AUTHOR]

Tick Hill gold deposit is a unique gold mineralisation style in the Mary Kathleen Fold Belt in the Mount Isa Inlier. The gold at Tick Hill is generally pure without silver and was formed during two discrete metamorphic-deformation events (D1 and D3). Early gold was observed as inclusions or coarse grains hosted within D1 peak-metamorphic diopside, scapolite and hornblende from the garnet–biotite–hornblende (tschemakite)–plagioclase (andesine)–quartz assemblage. Late gold is closely associated with bismuth selenide, chlorite, albite, sericite and K-feldspar, and formed during D3. The syn-D1 garnet–plagioclase–hornblende–quartz–biotite assemblage was used to constrain the pressure and temperature (P–T) conditions of metamorphism and mineralisation using the garnet–plagioclase–hornblende–quartz barometer and the hornblende–plagioclase, garnet–biotite and garnet–hornblende thermometers. The results show that peak metamorphism at Tick Hill reached P–T conditions of 6.0–7.6 kbar and 720–760 °C. These P–T conditions together with gneissic and migmatisation textures recorded in different rock types at the Tick Hill area indicate that the peak metamorphism preserved in the area occurred at the amphibolite–granulite facies, compared with the amphibolite facies at the southern Mary Kathleen and Eastern Fold Belt. The D3 chlorite, which formed during stage 2 to stage 4 mineralisation events, displays a wide range of compositions reflecting a gradual retrograde temperature change from ∼380 °C to ∼130 °C. The pressures during D3 could not be reliably determined, but the presence of various Bi-selenides suggests that towards the waning stages of D3, the rocks may have been exhumed to a pressure less than 1 kbar. The 1790–1770 Ma D1 peak metamorphism at Tick Hill reached 6–7.6 kbar and 720–760 °C. The 1525–1520 Ma D3 hydrothermal mineralisation at Tick Hill Deposit occurred at temperatures between ∼380 °C and ∼130 °C. The main D3 gold accumulation episodes at Tick Hill occurred at temperatures ranging from ∼380 to 160 °C. [ABSTRACT FROM AUTHOR]

The Dom Feliciano Belt is the South American part of an extensive Neoproterozoic orogenic system that developed during the late Cryogenian–early Cambrian close to the margin of southwest Gondwana. The link of its evolution with the tectonic processes in its African counterpart is still not well understood. P–T estimates, Lu–Hf garnet–whole-rock ages, U–Pb monazite SIMS ages and REE garnet and monazite data from samples of the Porongos and Passo Feio complexes indicate diachronous tectonic evolution of the central Dom Feliciano Belt foreland. Metasedimentary rocks of the eastern Porongos Complex reached previously estimated metamorphic peak conditions of ~ 560–580 °C and 5.8–6.3 kbar at 654 ± 2 Ma, based on Lu–Hf isochron garnet–whole-rock age data. This episode represents an early orogenic thickening in the foreland as a response to the beginning of the transpressive convergent evolution of the belt. The monazite age of 614 ± 6 Ma (U–Pb SIMS) is interpreted as associated with post-exhumation magmatic activity in the foreland and suggests that the eastern Porongos Complex was exhumed sometime between ca. 660 and 615 Ma. The main metamorphic and deformation event in the Porongos Complex's western region occurred at ~ 545–565 °C and 4.3–5.3 kbar at 563 ± 1 Ma (garnet–whole-rock Lu–Hf isochron age). The exhumation of this part of the foreland is dated using monazite crystallising during garnet breakdown and suggests retrograde metamorphism at 541 ± 7 Ma (U–Pb SIMS). The main metamorphic fabric in the Passo Feio Complex further to the west developed at 571 ± 2 Ma (garnet–whole-rock Lu–Hf isochron age) at 560–580 °C and 4.7–6.4 kbar. The western part of the Porongos Complex and the Passo Feio Complex have deformed at similar P–T conditions and apparent geothermal gradients at ca. 570–565 Ma. These regions record a second crustal thickening event in the Dom Feliciano Belt foreland and the orogenic front migration towards the west as a response to the onset of crustal thickening on the African side of this long-lived transpressive orogenic system. [ABSTRACT FROM AUTHOR]

Granite genesis is crucial to understanding the evolution of continental crust, yet many concerns about granite genesis remain not well answered, such as whether I-type granite contains metasedimentary components, what controls granite compositional diversity, and how granitic plutons are constructed. To explore these issues, we conducted a detailed study on the two-mica plagiogranite, tonalite, and biotite plagiogranite units of the Wujinxia composite pluton in the eastern Qilian orogen, NE Tibetan Plateau. These units comprise two-mica plagiogranite, tonalite (with diorite enclave), and biotite plagiogranite. Zircon U–Pb data reveal that three granitic units formed at ~ 487 Ma, ~ 464 Ma, and ~ 430 Ma, respectively. Magmatic and xenocrystic garnet were identified from the tonalite and biotite plagiogranite, respectively. The two-mica plagiogranite, tonalite, and biotite plagiogranite all belong to low-K series rocks (K2O/Na2O = 0.10–0.26), and were derived from deep crustal sources mainly consisting of juvenile mafic rocks, with involvement of minor metasedimentary rocks in the magma sources of the two-mica plagiogranite and tonalite. The diorite enclave within the tonalite was probably derived from an enriched mantle-derived basaltic magma. Mineral compositions, thermobarometric calculations, and whole-rock geochemical data indicate that the low-K intrusive units of the Wujinxia composite pluton resulted from multiple magmatic systems at different depths. The results suggest that I-type granites can contain metasedimentary components by partial melting of a mixed crustal source, and high-Mn content helps the preservation of high-Ca garnet within such rocks. For a composite pluton spanning a large compositional variation, its compositional diversity is jointly controlled by magma source composition, melting condition and thermal evolution of individual magma pulses, and the resulted assembly style during pluton construction. [ABSTRACT FROM AUTHOR]