Search Results (1,126)

This study focuses on the mineralogy and mineral chemistry of the accessory minerals occurring in the Kastoria pluton situated in NW Greece, which intrudes the Pelagonian nappe having crystallized during the Late Paleozoic (~300 Ma). The pluton consists of porphyritic granite (GR) that hosts mafic microgranular enclaves (MME) of monzonitic composition. Both lithologies contain quartz, microcline, plagioclase, biotite, secondary white mica, hornblende, and actinolite along with accessory minerals including titanite, epidote, allanite, apatite, zircon, and magnetite. Compared to the granite, the enclaves are richer in biotite, amphibole, and plagioclase but poorer in quartz and microcline. Mineral chemistry indicates a calc–alkaline affinity, consistent with the observed magmatic trends. Crystallization pressure, estimated at 3 kbar from Al in a hornblende barometer, suggests emplacement at mid-crustal levels. During the Alpine deformation, the pluton underwent low-grade greenschist to amphibolite-facies metamorphism, which partially overprinted the primary mineral assemblages. Magmatic titanite and allanite crystals are well preserved, showing only recrystallization features. Metamorphism produced tiny titanite needles and epidote replacing primary minerals (plagioclase, amphibole, and biotite). Later, hydrothermal alteration produced another generation of secondary epidote. Only a couple of epidote crystals preserve potential magmatic relict characteristics (euhedral habit, zircon inclusions, positive Eu anomaly, and sharp contact with primary minerals). These results provide insights into both the primary magmatic features and the subsequent metamorphic modification of the I-type Kastoria pluton within the Pelagonian domain. Full article

Quaternary lavas (ankaramite, basalt, basaltic andesite, andesite, dacite) from the Kamchatka, Kurile, Ecuador and Cascade volcanic arcs contain Cl-bearing mineral microinclusions in rock-forming minerals and groundmass volcanic glass. They are represented by chlorargyrite (with a variable amount of native Ag), Cu, Ag, Sn, and Zn compounds with Cl and S, Sn- and Pb-Sb oxychlorides compositionally similar to abhurite and nadorite, as well as bismoclite and Cl-F-apatite. The Cl-bearing compounds with chalcophile metals are best approximated by mixtures of chlorargyrite with Cu sulfides, malachite, or azurite. Some Cl-bearing solid microinclusions in magmatic rock-forming minerals could have formed from Cl-rich melts exsolved from arc magmas during differentiation. Alternatively, specific magmatic microinclusions may record the decomposition of primary sulfides in the presence of Cl-bearing magmatic volatiles. Post-magmatic Cl microminerals found in fractures, pores, grain contacts, and groundmass glass are most probably precipitated from hydrothermal fluids accompanying their emplacement at the surface and post-eruption transformations in active fumarole fields. Assemblages of Cl-bearing microminerals with native metal, alloy, sulfide, oxide, and sulfate microinclusions in arc lavas potentially record late-magmatic to post-magmatic stages of formation of the epithermal and possibly porphyry mineralization beneath arc volcanoes. Full article

Objectives: Despite the increasing scientific evidence regarding the application of Cranberries in dentistry, a comprehensive understanding of their potential benefits, active constituents, and mechanisms of action remains lacking. Consequently, this narrative review aims to meticulously analyze and consolidate the existing scientific literature on the utilization of Cranberries for the prevention and treatment of oral diseases. Materials and Methods: Electronic databases (PubMed, Scopus, and Web of Science) were searched up to October 2025. This review included in vitro, in vivo, and clinical research studies. A two-phase selection process was carried out. In phase 1, two reviewers independently screened titles and abstracts to identify potentially eligible studies. In phase 2, the same reviewers performed the full-text assessments of the eligible articles. Results: Among the 93 eligible articles, most assessed Cranberry use in Cariology (n = 28) and Periodontics (n = 26). Biofilm and microbial virulence factors (n = 46) were the most frequently studied topics. Cranberry extract (n = 32) and high-molecular-weight non-dialyzable material (NDM) (n = 23) were the most evaluated Cranberry fractions. Overall, Cranberry-derived compounds were identified as non-toxic and demonstrated promising antimicrobial activity against dental caries-related microorganisms in preclinical studies (n = 20). Regarding periodontal and peri-implant diseases, Cranberry demonstrated host immune modulator effects, counteracting the inflammatory and destructive mechanisms (n = 8). Additionally, Cranberries presented benefits in reducing the inflammation associated with periodontal disease and temporal mandibular joint lesions (n = 1). Regarding dental erosion, Cranberry inhibited dentin erosion (n = 4); however, no effect was observed on enamel lesions (n = 2). As an antioxidant agent, Cranberry showed effectiveness in preventing dental erosion (n = 18). Beyond that, Cranberry neutralized reactive oxygen species generated immediately after dental bleaching, enhancing bond strength (n = 2) and counteracting the oxygen ions formed on the tooth surface following bleaching procedures (n = 3). In osteoclastogenesis assays, A-type proanthocyanidins inhibited bone resorption (n = 1). In osteogenic analysis, preservation of hydroxycarbonate apatite deposition and an increase in early and late osteogenic markers were observed (n = 2). Conclusions: Cranberry bioactive compounds, both individually and synergistically, exhibit substantial potential for diverse applications within dentistry, particularly in the prevention and management of oral and maxillofacial diseases. This review provides insights into the plausible incorporation of Cranberries in contemporary dentistry, offering readers an informed perspective on their potential role. Full article

The Carboniferous coal seams in Northeast Kazakhstan remain insufficiently investigated, with a lack of comprehensive mineralogical and geochemical assessments necessary to understand the geological processes controlling coal quality. This study examines 15 coal samples from the Karagandy Coal Formation (KCF) at the Saradyr and Bogatyr mines using proximate and ultimate analyses, FTIR, XRD, SEM–EDS, ED-XRF, and ICP-OES, providing the first detailed comparison of mineralogical and geochemical characteristics—including depositional signals and inorganic constituent distribution—between these mines within the KCF. The coals exhibit an average ash yield of 24.1% on a dry basis, volatile matter of 21.6% on a dry and ash-free basis, and low moisture content of 1.1% (air-dry), with low sulfur levels of 0.7% in whole coal across both mines. Mineralogical composition is dominated by quartz and clay minerals, with minor pyrite, apatite, chalcopyrite, and rutile. Major oxides in the coal ash average 68.2% SiO₂ and 19.5% Al₂O₃, followed by Fe₂O₃, K₂O, and TiO₂ (3–12.1%). Among the 24 identified trace elements, Sm is the most abundant at 6.3 ppm with slight enrichment (CC = 2.8), Lu remains at normal levels (CC < 1), and most other elements are depleted (CC < 0.5). The Al₂O₃/TiO₂ ratios (3.8–10.8) indicate contributions from intermediate to mafic parent materials. The detrital mineralogy, parting compositions, and elevated ash content indicate significant accommodation space development during or shortly after peat accumulation, likely within a vegetated alluvial plain depression. These findings provide new insights into the depositional environment and coal-forming processes of the KCF and contribute to regional assessments of coal quality and resource potential. Full article

Iron oxide–apatite (IOA) deposits are important for the global supply of iron resources. Currently, there is considerable debate regarding the evolution of their mineralization mechanisms. The Heshangqiao iron deposit is a significant IOA deposit situated within the Ningwu ore district of the Middle–Lower Yangtze River Metallogenic Belt in China. This deposit exhibits distinct characteristics of multi-stage mineralization, forming disseminated ores, brecciated ores, and vein-type ores, from early to late stages. This study undertook a systematic elemental analysis of the magnetite and hematite from three mineralization stages of the Heshangqiao deposit. In the three mineralization stages of the Heshangqiao deposit, the elemental genesis indicators of ore genesis suggest that the hematite and magnetite both have magmatic hydrothermal genesis, characterized by high Ti and low Mg/Al and relatively high Ti and low Ni/Cr, respectively. The Cr and Sn contents of magnetite and hematite exhibit similar variation from the first to third mineralization stage, with an increase followed by a subsequent decrease. Meanwhile, the contents of V, Co, Ni, and Mn in magnetite and hematite exhibited an opposite trend, declining from the first to the second stage but eventually increasing from the second to the third stage. These changes in the genesis indicator also suggest that the multiple mineralization stages of the Heshangqiao deposit are independent of one another. The replacement of magnetite by hematite in each mineralization stage is not caused by the superposition of subsequent fluids, but rather by the residual fluid. It is noted that in the replacement the elements Cr, Co, and Ga were minimally migrated. These elements remained relatively stable and can be considered new potential discriminant indicators for the genesis of iron oxides. Full article

Phosphate is a crucial non-renewable mineral resource, mainly utilized in producing fertilizers that support global agriculture. As phosphorus is an indispensable nutrient for plant growth, phosphate holds a key position in ensuring food security. While deposits are distributed worldwide, the largest reserves are concentrated in Morocco. The Benguerir phosphate mining in Morocco generates heterogeneous waste (i.e., including overburden, tailings, and phosphogypsum) that complicates management and valorization, which is the beneficial reuse or value recovery from waste materials (e.g., use in cover systems, buffering, or other engineered applications). Therefore, it is essential to characterize their mineralogical properties to evaluate their environmental impact and possibilities for reuse or site revegetation. To do so, we integrate VNIR–SWIR reflectance spectroscopy with HandHeld X-ray fluorescence (HHXRF) to characterize phosphate waste rock and assess its reuse potential. For this purpose, field samples (n = 104) were collected, and their spectral reflectance was measured using an ASD FieldSpec 4 spectroradiometer (350–2500 nm) under standardized laboratory conditions. Spectra were processed (Savitzky–Golay smoothing, convex-hull continuum removal) and matched to ECOSTRESS library references; across the dataset, library matching achieved mean RMSE = 0.15 ± 0.053 (median 0.145; 0.085–0.350), median SAM = 0.134 rad, median SID = 0.029, and mean R² = 0.748 ± 0.170, with 84% of spectra yielding R² > 0.70. In parallel, HHXRF major and trace elements were measured on all samples to corroborate spectral interpretations. Together, these analyses resolve carbonate–clay–phosphate assemblages (dolomite commonly dominant, with illite/smectite–kaolinite, quartz, and residual carbonate-fluorapatite varying across samples). Elemental ratios (e.g., Mg/Ca distinguishing dolomite from calcite; K/Al indicating illite) reinforce spectral trends, and phosphate indicators delineate localized enrichment (P₂O₅ up to 23.86 wt % in apatite-rich samples). Overall, the combined workflow is rapid, low-impact, and reproducible, yielding coherent mineralogical patterns that align across spectroscopic and geochemical lines of evidence and providing actionable inputs for selective screening, targeted material reuse, and more sustainable mine reclamation planning. Full article

Apatite is a key indicator mineral whose chemical signature can reveal the genesis and evolution of ore-forming systems. However, correctly interpreting these signatures requires a robust discrimination between apatite types formed by different geological processes, such as metamorphism and hydrothermal activity. This study aims to chemically characterize and genetically classify apatite samples from the Slyudyanka deposit (Siberia, Russia) to establish discriminative geochemical fingerprints for metamorphic and hydrothermal apatite types. We analyzed 80 samples of apatite using total reflection X-ray fluorescence (TXRF) and inductively coupled plasma mass spectrometry (ICP-MS). The geochemical data were processed using principal component analysis (PCA) and k-means cluster analysis to objectively discriminate the apatite types. Our analysis reveals three distinct geochemical groups. Metamorphic veinlet apatite is defined by high U and Pb, low REE, Sr, and Th, and suprachondritic Y/Ho ratios. Massive metamorphic apatite from silicate–carbonate rocks shows extreme REE enrichment and chondritic Y/Ho ratios. Hydrothermal–metasomatic apatite features high Sr, Th, and As, with intermediate REE concentrations and chondritic Y/Ho ratios. Furthermore, we validated the critical and anomalous Y concentrations in the metamorphic veinlet apatite by cross-referencing TXRF and ICP-MS data, confirming the reliability of our measurements for this monoisotopic element. We successfully established diagnostic geochemical fingerprints that distinguish apatite formed in different geological environments at Slyudyanka. The anomalous Y/Ho ratio in metamorphic veinlet apatite serves as a key discriminant and provides insight into specific fractionation processes that occurred during the formation of phosphorites in oceanic environments, which later transformed to apatites during high-grade metamorphism without a change in the Y/Ho ratio. This work underscores the importance of multi-method analytical validation for accurate geochemical classification. Full article

Bioactive glasses (BGs) are promising materials for enamel remineralization and caries management due to their ion-releasing ability and capacity to promote apatite formation. However, their clinical translation remains limited. Conventional BGs, such as 45S5, exhibit excellent bioactivity but are mechanically weak, prone to rapid ion burst release, and lack long-term stability. Recent advances—including secondary oxide incorporation (e.g., B₂O₃, ZnO), polymer–glass hybrids, and nanostructured systems like mesoporous BGs and RegeSi have improved reactivity, mechanical performance, and remineralization depth, though their durability under oral conditions is not yet established. BGs also display antibacterial activity by elevating local pH and releasing ions that inhibit cariogenic bacteria, but their broader ecological impact on the oral microbiome remains poorly understood. Emerging approaches such as halogen-modified BGs, particularly fluoride- and chloride-doped formulations, show dual benefits for remineralization and antimicrobial action, though supporting evidence is largely confined to in vitro studies. The absence of standardized protocols for assessing remineralization, ion release, and biofilm interaction further complicates cross-study comparisons and slows clinical adoption. Future progress will require interdisciplinary collaboration, standardized evaluation methods, and rigorous clinical validation to ensure that next-generation BGs can be safely and effectively integrated into dental practice. Full article

Bone is one of the most important organs of mammals, consisting of collagen and apatite. Various diseases, such as osteoporosis, can affect the components of bone tissue, their chemical composition and bone ultrastructure, which leads to changes in properties. In this paper, the effect of initial osteoporosis on the chemical composition of bone apatite and the ultrastructure of bone tissue from a mineralogical point of view is analyzed using rat femurs as an example. The chemical composition of bone apatite was studied using SEM, EDS and FTIR-ATR spectroscopy. The bone ultrastructure was examined using a transmission electron microscope. An increase in the content of carbonate ion in the position of the phosphorus group and a change in the orientation of apatite crystals inside mineral plates were revealed against the background of initial osteoporosis, which can affect not only the mechanical properties of bone, but also the stability of apatite under biological conditions. Full article

Bioactive glasses remain promising candidates for enhancing osseointegration on metallic implants. However, achieving a composition that combines controlled dissolution, cytocompatibility, and antimicrobial functionality remains an ongoing challenge. Building upon the prior structural and thermal characterization of boron-substituted 6P55 phosphosilicate glasses, this study investigates the biological consequences of incorporating 0, 5, 10, and 15 mol% B₂O₃ to determine their suitability as coatings for Ti6Al4V. Glass extracts were evaluated using L-929 fibroblast cultures (MTT assay and ImageJ-based cell counting), antimicrobial assays against Escherichia coli and Staphylococcus aureus using a semi-quantitative dilution-plating method, and SBF immersion studies to assess pH evolution, surface mineralization, and Ca/P ratio development. FTIR and SEM analyses revealed composition-dependent formation of phosphate-, carbonate-, and silicate-rich surface layers, with 5B exhibiting the most consistent early-stage hydroxyapatite-like signatures, supported by Ca/P ratios approaching the stoichiometric value. The pH measurements showed rapid alkalization for 5B and moderate buffering behavior at higher boron contents, consistent with boron-dependent modifications to network connectivity. Cytocompatibility studies demonstrated a dose- and time-dependent reduction in cell number at elevated B₂O₃ levels, whereas the 0B and 5B extracts maintained higher viability and preserved cell morphology. Antibacterial assays revealed strain-dependent and sub-lethal inhibitory effects, with E. coli exhibiting stronger sensitivity than S. aureus, likely due to differences in cell wall architecture and susceptibility to ionic osmotic microenvironment changes. When considered alongside previously published computational and physicochemical results, the biological data indicate that moderate boron incorporation (5 mol%) provides the most favorable balance between dissolution kinetics, apatite formation, cytocompatibility, and antimicrobial modulation. These findings identify the 5B composition as a strong candidate for further optimization toward bioactive glass coatings on Ti6Al4V implants. Full article

Placer deposits constitute important secondary resources for economically valuable minerals, including rare earth elements (REEs) and heavy minerals such as zircon, rutile, and ilmenite. In this study, representative samples from the Hantepe placer deposit (Çanakkale, Türkiye) were processed to investigate the occurrence, distribution, and beneficiation potential of REE-bearing minerals. The ore was subjected to size classification, followed by gravity concentration on a shaking table and subsequent magnetic separation using a low-intensity disc separator. The resulting products were characterized by X-ray diffraction and X-ray fluorescence. The dominant REE-host minerals were identified as titanite, zircon, apatite, monazite and, allanite, accompanied by magnetite, hematite, quartz, and feldspar as gangue constituents. The non-magnetic final concentrate achieved substantial upgrading of critical elements, with Ce increasing from 868 g/t to 5716 g/t, Nd from 308 g/t to 2308 g/t, and Zr from 1435 g/t to 9748 g/t. Additionally, the magnetic concentrate (7.0 wt.%) was strongly enriched in Fe₂O₃ (70.26%) and V (2359 g/t), indicating its potential suitability as an Fe–V source. Overall, the results demonstrate that combined gravity and magnetic separation constitutes an effective beneficiation strategy for critical mineral recovery from placer systems. These findings establish a strong basis for future pilot-scale studies and the techno-economic evaluation of the Hantepe deposit as an emerging source of strategic and industrially relevant heavy minerals. Full article

Small interfering RNAs (siRNAs) provide strong therapeutic potential due to their efficient gene-silencing properties; however, their instability limits clinical application. Nanoparticle carriers may overcome this problem; in particular, magnetic nanoparticles show great promise as they can be directed to the target sites by external magnetic fields, thus improving delivery efficiency and reducing off-target effects. In addition, magnetic nanoparticles offer a novel nanoplatform for theranostic applications, integrating siRNA delivery with magnetic resonance imaging and magnetic hyperthermia for synergistic diagnostic and therapeutic advantages. The present work reports the development of a novel platform based on biomimetic magnetic nanoparticles made of Fe(II)/Fe(III)-doped apatite (FeHA) nucleated and grown in the presence of cherry and pomegranate leaf extracts to enhance the colloidal stability and make it suitable for nucleic acid delivery under the guidance of magnetic fields. This approach allowed the obtention of FeHA suspension with increased negative zeta potential leading to very good stability. In addition, the functionalization with natural extracts conferred antioxidant properties also favoring the maintenance of the Fe(III)/Fe(II) ratio in the apatitic structure, inducing the superparamagnetic properties. To evaluate the delivery capability of the system, a model GAPDH-targeting siRNA molecule was employed. Its interaction with the nanoplatform was characterized by assessing loading capacity and release kinetics, which were further interpreted using mathematical modeling to elucidate the underlying release mechanisms. Full article

In this study, eco-friendly sheep hydroxyapatite (KHO) powder was produced from sheep femur bone waste. Hybrid composite powders were prepared by adding varying amounts of MgO and MgO–graphene to the produced sheep hydroxyapatite powders and sintering them at 1200 °C for 5 min using induction sintering. The physical, mechanical, microstructural, in vitro bioactivity, cell culture, and antibacterial properties were studied. According to the results of the study, the density and compressive strength values of the samples containing 1 wt.% MgO and 1 wt.% MgO–0.1 graphene (KHM1 and KHM1GRF0.1), which had the best density and compressive strength values, were determined to be 2.771 g/cm³–28.42 MPa and 2.636 g/cm³–26.25 MPa, respectively. According to the in vitro bioactivity test in simulated body fluid, these composites exhibited bioactivity, with a dense hydroxy carbona apatite layer forming. Moreover, according to the cell culture and antibacterial test results, it was determined that sheep-derived hydroxyapatite, resulting from induction sintering with MgO and graphene, exhibited excellent biocompatibility, enhanced osteogenic potential, and moderate antimicrobial activity. In summary, these sheep hydroxyapatite hybrid composites exhibited higher mechanical strength and excellent integrated biological performance, confirming their substantial potential as advanced biomaterials for bone regeneration. Full article

Guided bone regeneration (GBR) plays a key role in alveolar ridge augmentation and implant therapy, but the biological mechanisms governing its outcomes are not fully understood. Preclinical animal models provide critical insights that cannot be obtained in early human studies. Over the past 15 years, our group has developed and optimized a standardized rat calvarial GBR model using plastic caps, enabling reproducible and quantitative evaluation of bone regeneration through micro-computed tomography and histomorphometry. The present narrative review synthesizes the findings from our body of work. Our studies demonstrated that advanced substitutes such as hydroxyapatite/collagen composites and carbonate apatite provide favorable outcomes, indicating that local and systemic application of growth factors or parathyroid hormone can markedly enhance augmentation, and that barrier permeability critically modulates angiogenesis and osteogenesis. Moreover, systemic conditions such as nicotine exposure and estrogen deficiency profoundly compromise regenerative outcomes but can be partly mitigated by pharmacological interventions. Finally, regenerated bone within GBR spaces is biologically competent, although it remains less mature than native cortical bone. Together, these insights highlight the translational value of our GBR model and indicate the integration of spatial omics for the elucidation of the cellular mechanisms that will guide future regenerative strategies. Full article

Africa hosts numerous emerald deposits, among which Sumbawanga, located at the junction of Tanzania, Zambia, Congo, and Malawi, stands out as one of the significant localities. This study presents a comprehensive analysis of the gemological, spectroscopic, and inclusion characteristics of Sumbawanga (Tanzania) emerald samples utilizing techniques such as gem microscopy, UV-Vis-NIR spectroscopy, Raman spectroscopy, GEM-3000, and EPMA, etc. These emerald crystals look like rolled pebbles and display a bluish-green coloration. They contain fingerprint-like fluid inclusions, which occasionally encompass a circular bubble (the gas phase is CO₂). Sumbawanga emeralds are characterized by abundant mineral inclusions, including quartz, apatite, anhydrite, diaspore, chrysoberyl, rutile, hematite, and magnetite. Particularly diagnostic are the mineral inclusion of chrysoberyl twins and the assemblages of quartz and diaspore. Full article