Chrysotile, the fibrous form of serpentine, is characterized by the chemical formula Mg3Si2O5(OH)4. Over the past seventy years, significant research has focused on synthesizing chrysotile, initially for petrological studies and more recently for applications in nanotechnology, particularly high-purity chrysotile nanotubes and doped variants. Common synthesis methods involve hydrothermal reactions using cristobalite and periclase or magnesium hydroxide and silica gel mixtures. Most frequently used synthesis conditions generally include temperatures between 200 °C and 400 °C and pressures from 0.5 to 100 MPa, though these often result in impure chrysotile with unwanted phases. Despite the promise of doped chrysotile, natural fibers are often unsuitable for nanoscience due to foreign ions and mineral intergrowths. Recent studies explore the potential for creating isomorphic series as Mg3Si2O5(OH)4 – Ni3Si2O5(OH)4 or Mg3Si2O5(OH)4 - (Fe2+, Fe3+)3-2Si2O5(OH)4, examining the impact of nickel and iron on chrysotile's properties. This study provides a review of the reported synthesis methods for chrysotile, emphasizing the synthesis techniques, precursor materials, and the resulting crystal chemistry. The findings highlight the dynamic nature of chrysotile synthesis research, with implications for materials science, including the development of novel nanostructures and environmental remediation technologies.

Kiwifruit Vine Decline Syndrome (KVDS), first reported in Italy in 2012, is a severe disorder causing significant yield losses. This study investigates the mineralogical and geochemical characteristics of soils from two kiwifruit orchards in different areas of Lazio (Italy), exhibiting varying degrees of symptom severity (CTRL: no symptoms; INTER: moderate; KVDS: severe), to improve understanding of this syndrome. Soil samples were analyzed by X-ray Powder Diffraction (XRPD), thermal analysis (TG-DSC), X-ray Fluorescence (XRF), Transmission and Scanning Electron Microscopy with Energy-Dispersive Spectroscopy (TEM-EDS and SEM–EDS), and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Chemico-physical parameters such as pH, electrical conductivity (EC), and loss on ignition (LOI) were measured and evaluated statistically through two-way ANOVA and cluster analysis. The soils exhibited subacidic pH (6.0–6.7) and low to moderate electrical conductivity (EC ≈ 100–380 µS/cm), indicating moderately good natural fertility. Mineralogical and geochemical analyses reveal that KVDS is associated with profound alterations in soil composition. The decline manifests from two pedogenetic extremes: "immature" soils with interrupted weathering and instability (Site 1), or "hyper-mature" soils with intense halloysite formation, leading to waterlogging and salt stress (Site 2). In both cases, a fundamental deviation from a healthy mineralogical equilibrium may represent a key factor associated with vine decline. The findings reveal clear mineralogical and geochemical differences between KVDS-affected and healthy orchards. These results provide insights that may support the development of targeted soil and water management strategies to prevent the onset of KVDS and mitigate its severity.

This study investigates the shallow ground heat exchange capability in the highly industrialized Gioia Tauro Plain (Southern Italy), integrating geological, hydrogeological, thermal, and geochemical data to assess the feasibility of both closed-loop and open-loop systems associated to geothermal heat pumps. For closed-loops the G.POT method was applied, enabling the calculation of extractable thermal energy based on soil properties and climatic conditions. For open-loops a comprehensive analysis was conducted using aquifer transmissivity, hydraulic conductivity, and geochemical features to identify the most suitable sectors. For the latter systems, a newly developed Geothermal Potential Viability Index was also proposed for a simplified system evaluation. Results show that the north-western sector of the plain has the highest suitability for closed-loop installations, due to high thermal conductivity and shallow water table. In contrast, areas near the Mesima and Budello river mouths exhibit physicochemical limitations for open-loop use, such as calcite oversaturation, high salinity, and elevated trace metal concentrations, which may significantly reduce the efficiency of open-loop systems. This integrated assessment provides a robust tool for energy planning, helping to identify high-potential zones while accounting for environmental risks and economic constraints.

The structural evolution of forsterite (Mg₂SiO₄) upon heterovalent coupled substitution with Li⁺ and Fe³⁺, forming the solid solution Mg(₂₋₂ₓ)LiₓFe³⁺ₓSiO₄, has been investigated up to 𝑥 ≈ 0.30. Single crystals were synthesized via high-temperature flux growth and characterized by single-crystal X-ray diffraction. Crystal structure refinements confirm a 2Mg²⁺ = Li⁺ + Fe³⁺ substitution, where Li⁺ occupies the smaller, less distorted M 1 octahedron, while Fe³⁺ occupies the larger M 2 octahedron, in agreement with charge-balance and bond-valence constraints. This substitution induces a linear contraction of the unit-cell volume, driven primarily by a decrease in the c -parameter, while concurrently causing a systematic expansion of the M 1 octahedron and a contraction of the M 2 octahedron. All measured structural parameters— such as mean bond distances, polyhedral volumes, and distortion indices—vary linearly with composition, indicating a continuous virtual solid solution up to x = 1.00. Extrapolation of the trends and subsequent Distance Least-Squares modelling predict a structurally viable atomic arrangement for the hypothetical LiFe³⁺SiO₄ endmember, which is crystal-chemically feasible as well as comparable to the known LiScSiO₄ olivine-type structure. These findings address conflicting literature reports by demonstrating that the olivine structure can accommodate the complete Li⁺ + Fe³⁺ ↔ 2Mg²⁺ substitution, thereby supporting the potential of LiFeSiO₄-type compounds as candidate cathode materials for lithium-ion batteries.

The present study investigates the hydrothermal synthesis of undoped talc and talc doped with Mn2+ and Ni2+ cations, to probe the effectiveness on stoneware tiles sintering. Undoped, Mn-and Ni-doped talc samples were synthesized at constant pressure (2 kbar) and reaction time (160 h), under different hydrothermal conditions (temperatures of 300 degrees C and 650 degrees C, pH values of 5 and 7). Characterization techniques including Powder X-Ray Diffraction (PXRD), Scanning and Transmission Electron Microscopy coupled with Energy Dispersive Spectroscopy (SEM/EDS, TEM/EDS), Differential Scanning Calorimetry (DSC), and micro-Raman Spectroscopy (mu R) were employed to analyse the starting materials, synthesized products as well as stoneware tiles. The study revealed a direct correlation between the amount of NiO in the initial mixture and the presence of Ni-dopant in the resulting talc, yielding a full substitution of Mg2+ by Ni2+ and the consequent formation of Ni3Si4O10(OH)2. However, in the same experimental conditions, the formation of Mn3Si4O10(OH)2 is not achieved. Indeed, a saturation point for Mn2+ doping in talc has been identified, and its nature will be discussed. Furthermore, undoped-talc, Mn doped talc and Ni-talc have all been employed for the sintering of stoneware tiles. This present study demonstrates that Mn-and Ni-doped synthetic talc act as highly effective fluxing agents in stoneware tile bodies. Their addition promotes a more rapid consumption of crystalline phases, specifically albite, at lower firing temperatures compared to undoped talc. Notably, Mn2+-doping (even at low concentration of dopant) exhibits a more pronounced effect than Ni-doping. This process may offer a direct pathway to substantial energy and cost savings in industrial ceramic production.

Multicomponent geothermometry is a critical tool for estimating subsurface temperatures, but its accuracy can be significantly affected by the crystalline order-disorder state of minerals, which is often inadequately represented in standard thermodynamic databases. This study addresses this limitation by systematically incorporating variably ordered forms of key secondary minerals. We demonstrate that the availability of these forms, characterized by the order-disorder parameter Q, and the ability to select the mineral form with the right degree of order-disorder, leads to substantial improvements in the application and reliability of multicomponent geothermometry. This was achieved by first calculating the thermodynamic properties of disorder (Gibbs free energy, enthalpy, entropy, volume) for a suite of common secondary minerals including feldspars (adularia, albite, anorthite), carbonates (calcite, dolomite, ankerite), micas (muscovite, paragonite, phlogopite), iron oxides (hematite, magnetite), iron sulfides (pyrrhotite), sphene, and quartz using Landau theory, for Q values ranging from 0 (completely disordered) to 1 (completely ordered). These data were then used to significantly expand the SUPCRT92 thermodynamic database and subsequently the PHREEQC-LLNL database. The enhanced geothermometric approach, utilizing PHREEQC with the modified database, was then applied to two formation waters from the Temblor Formation in the Kettleman North Dome oil and gas field, California, and fifteen geothermal waters from the geothermal fields of Reykjanes and Svartsengi (Iceland), Tauhara (New Zealand), Miravalles (Costa Rica), and Kizildere (Turkey). In these case studies, selecting the mineral form with the appropriate Q value resulted in improved convergence of mineral saturation indices (log Q/K) at plausible equilibrium temperatures. This often led to better agreement with independently estimated reservoir conditions or known authigenic/hydrothermal mineral assemblages compared to calculations using only fully ordered or unspecified mineral forms. This achievement is crucial, as crystalline order-disorder significantly impacts the thermodynamic stability and reactivity of many solid phases. These minerals, present as diagenetic (authigenic) phases in oil-and-gas field aquifers and as hydrothermal alteration products in geothermal reservoirs, play a key role in dictating fluid-rock equilibrium. Neglecting their specific order-disorder state can therefore lead to erroneous temperature estimations and misinterpretation of reservoir conditions. The results underscore the importance of considering order-disorder phenomena for robust geochemical modeling and highlight the utility of the expanded thermodynamic dataset for future geothermometry applications.

The long-term toxicity of mineral fibres is closely related to their biodurability and surface reactivity, which are in turn strongly influenced by mineral dissolution and surface alteration in lung fluids. We investigated dissolution rates and nanoscale structural, morphological and surface chemical modifications of fibrous antigorite, a non-regulated serpentine polymorph of uncertain pathogenicity, amphibole asbestos (crocidolite and tremolite) and chrysotile, after incubation in artificial lysosomal fluid at pH 4.5, simulating the acidic environment of alveolar macrophages. Fibres were incubated at 37 °C for up to 4 weeks; elemental release was quantified by ICP-OES, and recovered fibres were characterized by PXRD, XPS, FE-SEM, AFM, and TEM. All fibres dissolved incongruently, with preferential leaching of octahedrally coordinated cations and Fe mobilization promoted by citrate complexation. Chrysotile dissolved extensively and became progressively amorphous, consistent with its high specific surface area and preferential removal of Mg from outer octahedral layers. When Si-based dissolution rates are normalised to specific surface area, fibrous antigorite displays biodurability comparable to chrysotile and at least one order of magnitude lower than amphibole asbestos. Among amphiboles, tremolite dissolves more slowly than crocidolite, for which surface erosion exposes underlying Fe(II)-rich layers. Despite the simplified, acellular nature of the ALF model, our results show trends in incongruent dissolution, Fe mobilisation and surface amorphisation consistent with in vivo toxicological observations. Integration of ALF-based mineralogical and geochemical data with targeted cellular and in vivo studies may provide a more robust mechanistic framework for understanding the long-term toxicity of both asbestos and currently unregulated fibrous minerals.

Asbestos that occurs in the environment and has not been extracted for commercial purposes is commonly referred to as Naturally Occurring Asbestos (NOA). Research has shown a higher-than-expected incidence of mesothelioma in populations residing near NOA sites across California, Greece, Turkey, Cyprus, Corsica, and New Caledonia. In Italy, in the area around Pollino Massif (Basilicata region), a total of 124 mesothelioma cases were documented among population living in the villages of Castelluccio Superiore and Inferiore, Lauria, Latronico, Episcopia, San Severino Lucano, and Francavilla in Sinni. In this work for the first time, we report the morphological and chemical structural characterization of asbestos tremolite samples from the NOA outcrops in the Pollino area (Basilicata region). The detailed sample characterization has been attained by using a multi-analytical approach (EMP, SEM-EDS, TEM-EDS, Mössabuer, X-ray powder diffraction, and thermal analysis). Morphological investigation highlighted that a significant fraction of each sample (ca. 50

This study investigates the transformation of ultramafic rocks into serpentinite, carbonated serpentinite, talcose serpentinite, and pure talcose rocks within Cabo Ortegal ultramafic complex (NW Spain). We aimed to characterize mineralogical, geochemical, and isotopic changes driven by fluid-rock interactions and assess environmental implications. An integrated approach including Petrographic Microscopy, X-ray Diffraction, Transmission Electron Microscopy, Thermal Analysis, ICP–MS, and Stable Isotope (δ¹⁸O, δ¹³C, D/H) analyses was applied. Results reveal a stepwise evolution with SiO₂ and Al₂O₃ enrichment, depletion of Fe, Mg, Mn, and volatiles, and notable trace element variations (Sr, Li, Zr, Nb, Th, U). Isotopes indicate alteration mainly by metamorphic fluids, with minimal meteoric or marine influence. Talc formation occurs via low-temperature hydrothermal processes involving SiO₂- and CO₂-rich fluids, mobilizing potentially toxic elements (e.g., Cr, Ni, Co), raising environmental concerns near abandoned quarries. Although serpentinites have industrial potential, their heterogeneity from ongoing transformation complicates their use. Enhancing our understanding of serpentinite alteration is crucial for effective resource management and environmental protection. Although Cabo Ortegal has been extensively studied, the significance of serpentinite transformation remains insufficiently explored. The findings emphasize the need for detailed petrological and geochemical investigations to balance resource utilization with environmental stewardship in ultramafic terrains. This study demonstrates that talcose rocks are unsuitable for pharmaceutical or cosmetic applications but possess artisanal potential, promoting the tourism of a newly recognized UNESCO Global Geopark. Improving the scientific knowledge of the serpentinites and their evolution can help to increase the knowledge on the ultramafic massif but also may help to promote industry in the area as well as to preserve the environment.

Among the current global challenges, the research of new practices aimed at mitigating soil impoverishment, exacerbated by the pressing climate changes, is the most urgent. Studying soil organic matter (SOM) ecological dynamics and comparing the conventional intensive farming practices with the emerging alternative sustainable ones can represent a key indicator in soil health investigation, helping to find new guidelines for conservative agrosystems management. In this study, the soil from a Mediterranean olive orchard, with both sustainable (S-mng) and conventional (C-mng) land use for 21 years, was investigated for its physicochemical properties, with a particular attention to the soil organic matter from aggregates (SOM-A) and its interaction and distribution at different soil depths. Significantly higher amounts of total carbon (+50.7 %) and nitrogen (+74.9 %), as well as of SOM-A aromatic component (+76.0 %), were detected in the topsoil layer (0-5 cm) of the S-mng, compared to the C-mng, a sign that the organic matter from surface deeply seeps slowly. This evidence was highlighted especially in micro-aggregates (< 0.063 mm) of the Smng, compared to the C-mng (C = +59.3 %; N = +86.7 %; SOM-A aromatic component = +87.7% in the Smng). This trend was also reflected in an increase in the bacterial abundance and in a different accumulation of organic compounds deriving from microbial fermentation processes in Smng soil, as highlighted by the SOM-A qualitative characterization by metabolomics. The soil mineralogical analysis showed that minerals maintained a higher crystallinity in the S(mng )than in the C-mng, where soil tillage promoted their alteration. Moreover, Fourier-transform infrared (FTIR) spectroscopy analysis highlighted that soil disturbance in the C-mng can affect SOM distribution, creating different spatial distributions in the particle aggregates and soil depths. Distinguishing SOM quantity, quality, and interaction with mineral components can help to understand its degradability and dynamics, both essential for mitigating the effects of climate change and promoting land protection.

Growing requirements in the field of environmental protection and waste management result in the need to search for new and effective methods of recycling various types of waste. From the perspective of technical and natural sciences, the disposal of hazardous waste, which can lead to environmental degradation, is of utmost importance. A particularly hazardous waste is asbestos, used until recently in many branches of the economy and industry. Despite the ban on the production and use of asbestos introduced in many countries, products containing it are still present in the environment and pose a real threat. This paper presents the results of research related to the process of asbestos neutralization, especially the chrysotile variety, by the thermal decomposition method. Changes in the mineralogical characteristics of asbestos waste were studied using the following methods: TG-DTA-EGA, XRD, SEM-EDS and XRF. The characteristics of the chrysotile asbestos sample were determined before and after thermal treatment at selected temperatures. The second part of the study focuses on the kinetic aspect of this process, where the chrysotile thermal decomposition process was measured by two techniques: ex situ and in situ. This study showed that the chrysotile structure collapsed at approximately 600–800 °C through dehydroxylation, and then the fibrous chrysotile asbestos was transformed into new mineral phases, such as forsterite and enstatite. The formation of forsterite was observed at temperatures below 1000 °C, while enstatite was created above this temperature. From the kinetic point of view, the chrysotile thermal decomposition process could be described by the Avrami–Erofeev model, and the calculated activation energy values were ~180 kJ mol−1 and ~220 kJ mol−1 for ex situ and in situ processes, respectively. The obtained results indicate that the thermal method can be successfully used to detoxify hazardous chrysotile asbestos fibers.

The work aims to estimate natural greenhouse gas emissions from soils in the Sibari Coastal Plain (Southern Italy), to understand (i) the contribution in terms of the total amount of CO2 and CH4 emitted in non-volcanic areas, (ii) the relationship among emitted gas, land use, organic matter and tectonic structures, and (iii) their potential environmental implications. Data were elaborated with statistical and geostatistical methods to separate the different populations and obtain prediction and probability maps. Methane fluxes had values consistently below the detection limit (0.032 g ∙ m−2 ∙ d−1) except for three measurement points randomly distributed along the plain. Statistical and geostatistical methods allowed to discriminate three main CO2 flux populations: (i) high-flux population (Pop. B - mean value of 63.65 g ∙ m−2 ∙ d−1), located near the mouth of the Crati River and related to the massive presence of buried organic matter in the form of peat; (ii) medium-flux population (Pop. A2 - mean value of 8.37 g ∙ m−2 ∙ d−1) which is the result of soil respiration, and (iii) low-flux population (Pop. A1 - mean value of 1.85 g ∙ m−2 ∙ d−1) due to areas where low permeability or increases in saturated aquifer thickness may control the overall flux.In the study area, a total CO2 emission of about 2671 t ∙ d−1 was calculated, which, if compared to the average total flux expected for simple soil respiration (1284 t ∙ d−1), represents a non-negligible value in the total Carbon balance. Finally, the comparison with representative normalized fluxes from volcanic and non-volcanic areas confirms the critical role of coastal plains in total atmospheric CO2 emissions. The proposed approach can be applied to areas with comparable or different geological and climatic settings to trace their contribution in terms of greenhouse gas release to the atmosphere.

Reaction Path Modelling was used to calculate the fluxes in terms of solutes and CO2 consumption during the water-rock interaction process at the basin-scale, considering the current and future climate scenarios (temperature and atmospheric CO2 concentration) and two types of solid reagent (Silicate Solid Reagent-SSR and Carbonate-Silicate Reagent C-SSR). Two modelling were performed considering solid reagents and simulating their weathering in the current climate scenario and two other simulations were developed to consider the future climate scenario (Representative Concentration Pathways - RCP 8.5). The study highlights that although the higher temperature promotes an increase of total dissolved ions (TDS) into riverine waters, the higher temperature also causes a decrease in precipitation and, thus, in the runoff. This condition will lead to a reduction in weathering rate and CO2 consumption at the basin scale. The main indirect effect of a negative CO2 consumption budget is a further increase in CO2 atmospheric concentration.

A series of Li + /Fe 3+ -doped enstatite crystals of composition Mg (2–2 x ) Li x Fe x Si 2 O 6 were synthesized and structurally characterized. Under the selected experimental conditions, we grew three crystals of Pbca orthopyroxene (OPX: x = 0.270–0.313) and two crystals of Pbcn protopyroxene (PPX: x = 0.156–0.164) using the flux-growth technique. The observed variation in the polyhedral volume and distortion of the M 2 octahedron as a function of Li/Fe 3+ doping suggests the presence of an upper limit, at least for the OPX samples. The same linear relation was observed between the polyhedral volume and 〈 M 1—O〉 bond length across all analysed samples, including the endmembers protoenstatite (PEN), orthoenstatite (OEN) and LiFe 3+ Si 2 O 6 . It seems that the M 2 octahedron plays a crucial role in stabilizing the pyroxene topology in either the PEN or the OEN form, because the PPX and OPX samples show two distinct linear relations between the M 2O 6 polyhedral volume and 〈 M 2—O〉, with the PPX trend converging toward the parameters of the LiFe 3+ Si 2 O 6 endmember, whereas the OPX trend, including OEN, diverges largely from these parameters.

We evaluated the geothermal resources of Vulcano Island considering the available geological, geochemical, and geophysical information in the framework of the conceptual model of La Fossa magmatic-geothermal system. Having ascertained that the shallow groundwaters of the Vulcano Porto plain are heated by geothermal steam and gases and are not directly impacted by magmatic fluids, we have adopted the CO2Pand temperature distribution in these shallow groundwaters to delimit the areal extension of the underlying geothermal aquifer, which is 0.777 km2 and 0.752 km2 based on the CO2Pand temperature maps respectively, in agreement with the area from MT data, 0.7 km2. The revised volume method was used considering the specific productivity of liquid-dominated geothermal systems, 40 t center dot h-1 center dot km-3, and assuming that the geothermal aquifer has a thickness of 2.8 km and a temperature of 200-275 degrees C. The hourly production rate of geothermal fluids resulted to be in the range 84.2-87.0 t center dot h-1, while the extractable thermal and electrical powers turned out to be 25 +/- 6(1 sigma) MWt and 8.3 +/- 2.0 MWe, respectively. Drilling of one or two production wells and one reinjection well (depth in the order of 1.5-2.0 km) could be therefore a suitable technical solution.

Naturally Occurring Asbestos (NOA) has drawn the attention worldwide when investigation revealed an increased incidence of malignant mesothelioma in population living near NOA sites. In Basilicata region (South Italy), population living in the villages of Castelluccio Superiore and Inferiore, Lauria, Latronico, Episcopia, San Severino Lucano, and Francavilla in Sinni may be considered at high risk of asbestos exposure because these villages are either surrounded by or built on NOA-rich ophiolitic outcrops. In this work we investigated an asbestos tremolite sample coming from the ophiolitic rocks outcropping in the quarry of Iacolinei, widely used in the past to extract aggregates for various applications. A detailed mineralogical characterization has been attained by using a multi-analytical approach (EMPA, SEM-EDS, TEM-EDS, Mössbauer, µ-Raman, X-ray powder diffraction, and thermal analysis). Morphological investigation highlighted that the sample is composed of long fibers (> 5 µm) with a significant fraction (ca. 55

Potentially toxic elements (PTEs) host in asbestos elongate mineral particles is one of the factors which have been invoked to explain their toxicity/pathogenicity effects.This study quantifies and compares these elements in terms of major, minor and trace element concentrations (Si, Mg, Ca, Al, Fe, Mn, Cr, Co, Ni, Cu, Zn, Be, V, As, Rb, Sb, Ba, Pb, Sr) in various types of asbestos using micro X-ray fluorescence (μ-XRF) and inductively coupled plasma mass spectrometry (ICP-MS), in order to understand how they contribute to asbestos-related diseases. Chrysotile, tremolite asbestos and actinolite asbestos extracted from the Gimigliano-Mount Reventino Unit (Calabria Region, Southern Italy) were used for this study.Among the investigated minerals high concentrations of Cr (171 ppm) and Be (2.9 ppm) were found in tremolite asbestos and chrysotile respectively. When calculating the pseudo-total concentrations of trace elements in the samples, the largest amounts were detected in tremolite asbestos, followed by actinolite asbestos and chrysotile. However, since other metals such as Mn and Fe (minor elements) are known to induce toxicity, and considering their input to the overall balance, actinolite contained the largest amount of PTEs and in this case chrysotile proved to be more toxic than tremolite asbestos. Furthermore, the potential leaching of PTEs, released by chrysotile, tremolite and actinolite asbestos-containing rocks, into the soil and water supply is also discussed. Since asbestos elongate mineral particles can be widespread in the environment (i.e. rocks, soil, water), it is essential to quantify the toxic elements present in asbestos elongate mineral particles in order to prevent asbestos-related diseases. The knowledge obtained from this study will provide us with a better understanding of asbestos-related lung cancer.

Olivines are naturally occurring silicates consisting of isolated (SiO4)4- tetrahedra linked through M1O6 and M2O6 octahedra. In this study, we report the structural and crystal-chemical characterization of synthetic olivine crystals containing up to 25% Li-Fe3+ synthesized using the flux growth technique. Based on site scattering, and mean bond lengths, and charge neutrality of the chemical formula, we found a perfect ordering of Li and Fe3+ at the two distinct M1 and M2 sites. Unrestrained linear extrapolation to a hypothetical isostructural LiFe3+(SiO4) composition aligns well with the tabulated ionic radii of Li and Fe3+. Comparison made with the isostructural LiSc(SiO4) reveals that the Li-centered M2O6 octahedron has a significant capacity to distort in order to accommodate structural stresses, due to the relatively weak Li-O bond, while still achieving a bond valence sum that closely matches the formal charge of Li+. This behavior suggests the potential feasibility of an extended Li + Fe3+ for 2 Mg coupled substitution within the olivine structure. The reported structure of the LiFe3+(SiO4) endmember in the literature, despite its apparent matching of cell dimensions and space group with olivine, exhibits extremely unconventional crystal chemical features, raising questions about its validity. Given the importance of the suitability of Li-insertion in LiFeSiO4 as electrodes in rechargeable Li-ion batteries, further studies are needed to investigate its crystal structure and crystal chemistry.

In this work, the old Lungro mining site was studied by applying two classification methods (Brilha and IELIG Method), considering the site-specific scientific, educational, touristic, and degradation aspects, to promote it as a geosite. The results were compared with those from other worldwide areas, and a potential re-evaluation in the tourism sector was suggested, considering historical data and geological issues. The methods used evaluate the Lungro site an average score from a scientific perspective, and from high to very high for the tourist-educational aspects. On the contrary, lower scores were found regarding the degradation of the site due to natural phenomena, led to a lower total score. The obtained results are comparable with other similar restored mining areas, located in various parts of the world which today represent important geotourists sites recognized internationally. Based on these results, the safest, most cost-effective, and straightforward way to preserve and restore the site is by creating a “Geotourism Route.“. This choice would increase awareness of the area, providing the general public, including the curious and “non-experts”, with an understanding of various geological processes and the extensive history of the mine. A campaign to promote and preserve the Lungro site as a geoheritage will be encouraged, with significant implications for tourism at the local, national, and international levels.