University of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Strip mining of stratiform deposits with thick overburden: environmental challenges and constraints to sustainable extraction24925810683010.22059/ijmge.2026.404895.595329ENRedouaneOubahLaboratory of Applied Geophysics, Geotechnics, Engineering Geology and the Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.0009-0005-0891-6886YoussefZerradi Laboratory of Applied Geophysics, Geotechnics, Engineering Geology and the Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.0000-0003-0192-8225LatifaOuadifLaboratory of Applied Geophysics, Geotechnics, Engineering Geology and the Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.0000-0002-4613-1124AnasDriouchLaboratory of Applied Geophysics, Geotechnics, Engineering Geology and the Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.0000-0003-1292-4692AmineSoufiLaboratory of Applied Geophysics, Geotechnics, Engineering Geology and the Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.0009-0002-6137-9459Journal Article20251024The resource extraction industry relies heavily on strip mining to produce various minerals. Its popularity arises from its cost-effectiveness, making it a key surface mining method to meet the growing global demand for raw materials. The depletion of shallow ore deposits has led to an increased reliance on strip mining under extremely thick overburden layers, intensifying the environmental impact of mining operations. The first aim of this study was to evaluate the environmental effects of mining operations under these complex conditions, with a particular focus on their impact on land use, energy consumption, and climate change. Drawing upon multiple case studies, the research quantitatively explores how increasing overburden thickness affects the technical feasibility, energy demand, and footprint of mining activities. This analysis highlights the delicate balance between geological conditions and mining strategy which offers new insights into optimizing extraction efficiency while minimizing ecological disturbance. The feasibility of the utilization of an artificial neural network (ANN) based conceptual model was then explored to outline a predictive framework for environmental impacts under these conditions, intended to support future practical applications by combining the important operational factors studied with site-specific characteristics. The conception of the ANN model was structured with one hidden layer that is meant to capture complex connections between key mining factors and each one of the expected outcomes.https://ijmge.ut.ac.ir/article_106830_2affe3646f5f011855973dc2b45a3335.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Efficient computation of the ERT sensitivity matrix via a semi-analytical approach25926510687410.22059/ijmge.2026.404658.595327ENYosraAzadiInstitute of Geophysics, University of Tehran, Tehran, Iran.0009-0005-4192-3076RezaGhanatiInstitute of Geophysics, University of Tehran, Tehran, Iran.0000-0003-1138-7442MahdiFallahsafariInstitute of Geophysics, University of Tehran, Tehran, Iran.0009-0008-6449-0463Journal Article20251020The partial derivative of data with respect to model parameters also known as the Jacobian or sensitivity matrix plays a significant role in electrical resistivity tomography inversion by which the influence of a differential model parameter change on individual measurements is denoted. Hence, providing the sensitivity matrix is a crucial step in the 2D/3D electrical resistivity tomography inversion process. While the sensitivity matrix is extensive, calculating each individual sensitivity associated with every cell (or model parameter) is computationally expensive which may not feasible in the case of large model space. There is always a challenge in keeping the accuracy of the analytical method while reaching a reasonable computing time. This paper proposed a semi-analytical method to reduce the sensitivity matrix calculation time compared to the conventional method. The integration over the signal contribution which is the most time-consuming part of the sensitivity calculation, was solved using the Modified Gauss–Legendre quadrature (MGLQ) method. To verify the functionality of the proposed approach, the sensitivity distribution of an isotropic and homogeneous model was displayed for three common electrode configurations, i.e., pole-pole, dipole-dipole, and Wenner arrays. Our investigation demonstrate that the sensitivity values vary spatially depending on the type of electrode positions. Furthermore, when employing a semi-analytic scheme, the proposed algorithm delivers a substantial reduction in computation time while maintaining acceptable accuracy in the calculated values. The presented method can be readily extended to other electrode configurations with arbitrary subsurface conductivity distribution.https://ijmge.ut.ac.ir/article_106874_2604fa0a1df542f33fc9663187b38dde.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Airborne time-domain electromagnetic investigation of the Granisle polymetallic deposit: qualitative interpretation and rapid conductivity-depth imaging26727610687510.22059/ijmge.2026.406956.595337ENMohammad SalehAhmadiSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.AliJafarabadiSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.MaysamAbediSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.0000-0002-5365-0694AliMoradzadehSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.0000-0001-9077-8278Journal Article20251124Airborne time-domain electromagnetic (ATEM) surveys have emerged as one of the most effective tools for detecting conductive structures and concealed mineral targets, achieving remarkable accuracy and efficiency in recent years. In this study, airborne electromagnetic data from the QUEST-West project were utilized to reconstruct the three-dimensional geometry of alteration and mineralization zones within the Granisle porphyry Cu–Au deposit in the Babine district of British Columbia. Qualitative analysis of off-time channels and the Late Time Decay Constant (τ) map revealed three prominent conductive zones with a northeast–southwest trend. In addition, conductivity-depth imaging (CDI), implemented via a fast approximate transform, was applied to generate independent depth sections for each flight line, which were subsequently merged through multidimensional interpolation into a quasi–three-dimensional conductivity model. The CDI results indicate the presence of a focused conductive body with a shallow top (on the order of tens of meters below surface) and a significant vertical extent, spatially coincident with the historic open pit at the Granisle deposit—a geometry consistent with the known distribution of mineralized zones and vein networks at Granisle. By circumventing computationally intensive inversion procedures, this approach provides a stable and geologically coherent first-order image of subsurface conductivity and can serve as a reference model for quantitative inversion, drill targeting, and exploration decision-making in the historically mined Granisle porphyry deposit.https://ijmge.ut.ac.ir/article_106875_0a895c42ef6e79b2061650dd3dd5ce42.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Examining the effect of physico-mechanical and petrographical properties of granite building stones on the stone surface quality after polishing process27728510687810.22059/ijmge.2026.408114.595344ENSeyed JalilMousaviDepartment of Mining Engineering, Isfahan University of Technology, Isfahan, Iran.EbrahimGhasemiDepartment of Mining Engineering, Isfahan University of Technology, Isfahan, Iran.AliFarhadianMining Group, Faculty of Engineering, University of Jiroft, Jiroft, Iran.AliBameriDepartment of Mining Engineering, Isfahan University of Technology, Isfahan, Iran.Journal Article20251213The purpose of this study was to examine the effect of physico-mechanical and petrographic properties of building stones on their surface quality after the polishing process. To do this, a laboratory investigation was performed on 15 different types of Iranian granite building stones, including petrographic analyses, physico-mechanical evaluations, and polishing tests. Moreover, to assess the stone surface quality, surface roughness and gloss were measured before and after the polishing process, based of which three indices were proposed for quantifying the surface quality improvement, including gloss improvement index (GII), roughness improvement index (RII), and quality improvement index (QII). Then, the correlations between these three indices with the physico-mechanical and petrographic properties of stone were investigated. The results revealed that the Schmidt hammer hardness (SCH) is the main parameter that affects the proposed indices. Finally, non-linear regression analyses were applied for development of predictive equations for the GII, RII, and QII based on the SCH. Predictive equations presented very good performance with determination coefficient (R2) values between 0.747 and 0.826. These results suggest that the predictive equations are suitable for practical applications and can be employed for the rapid assessment of stone surface quality after polishing process.https://ijmge.ut.ac.ir/article_106878_35096934893604bb59bf75cb0bce0a61.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Mixed-norm modeling of airborne tensor gravity and total field magnetic data to image the intrusion-related gabbroic budgell harbour stock28730110851710.22059/ijmge.2026.413985.595371ENFatemehDidarSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.MojtabaHosseiniSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.MaysamAbediSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.0000-0002-5365-0694VahidEbrahim Zadeh ArdestaniInstitute of Geophysics, University of Tehran, Tehran, Iran.0000-0003-3936-201XZahra SadatMohammadi SaroughiInstitute of Geophysics, University of Tehran, Tehran, Iran.Journal Article20260507This study examines the subsurface architecture of a gabbroic body located in the Newfoundland region (Newfoundland and Labrador, Canada) by analyzing tensor gravity and total magnetic intensity data. The primary objective is to assess the effectiveness of various regularization strategies within a mixed-norm inversion framework for improving the reconstruction of the geometry and physical property distribution of the gabbroic body and its associated anomalous zones. To this end, following initial preprocessing, the gravity and magnetic datasets were inverted under three scenarios employing mixed , and norm configurations, respectively, thereby enabling a comparative evaluation of the influence of sparsity versus smoothness constraints on inversion outcomes. The results demonstrate that sparser norms are more effective at delineating compact, high-contrast anomalous bodies, while smoother norms yield superior recovery of continuous structural features and regional background trends. A comparative analysis of the two datasets reveals that magnetic data exhibit greater sensitivity to variations linked to magnetic mineralization within the gabbroic body whereas gravity data offer more robust constraints on the overall geometry and density distribution of the body. All inversion experiments achieved stable convergence, and the resulting models successfully delineated both the primary structure of the body and its associated anomalous zones. Collectively, the findings of this study indicate that employing a mixed-norm inversion framework jointly with gravity and magnetic data constitutes an effective approach for reducing ambiguity and enhancing the interpretation of subsurface structures in complex geological settings, such as gabbroic intrusions.https://ijmge.ut.ac.ir/article_108517_1a03bbf2cb22f65a544ef279415d8e83.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Application of geophysical techniques to identify the causes of roadway instability in conductive ground (Fez region, Morocco)30331210868610.22059/ijmge.2026.403723.595328ENBrahimSalhiDepartment of Mechanical and Structural Engineering, National Graduate School of Arts and Crafts, Moulay Ismail University, Meknès, Morocco.0009-0003-4958-2793AhmedBenamaraDepartment of Mechanical and Structural Engineering, National Graduate School of Arts and Crafts, Moulay Ismail University, Meknès, Morocco.LhoussaineTarikDepartment of Geosciences, Faculty of Sciences and Techniques, Moulay Ismail University, Boutalamine, Morocco.0000-0003-1160-6844KhalidKramiDepartment of Mechanical and Structural Engineering, National Graduate School of Arts and Crafts, Moulay Ismail University, Meknès, Morocco.AhmedHamidiDepartment of Mechanical and Structural Engineering, National Graduate School of Arts and Crafts, Moulay Ismail University, Meknès, Morocco.MohammedRadouaniDepartment of Mechanical and Structural Engineering, National Graduate School of Arts and Crafts, Moulay Ismail University, Meknès, Morocco.Journal Article20251020Road instability in marly formations poses a major threat to infrastructure, as water saturation reduces soil-bearing capacity and promotes landslides and subsidence. To address this issue, this study applies an integrated geophysical approach combining electrical resistivity tomography (ERT) and the very low frequency electromagnetic (VLF-EM) method to identify the subsurface causes of pavement failures on three unstable road sections in the Fez-Meknes region (Morocco). Six ERT profiles were acquired along with VLF-EM surveys and subsequently validated by core drilling. The results reveal pronounced conductive anomalies extending to depths of approximately 15–20. These critical anomalies are characterized by very low resistivity values (ρ ≈ 1–5 Ω·m) and interpreted as water-saturated clayey–marly horizons. Moreover, VLF surveys delineate linear conductive zones, while ERT imaging highlights resistivity contrasts and their spatial distribution. Importantly, core drilling confirms that the most conductive zones (< 5 Ω·m) correspond to plastic clayey marls. Thus, this combined ERT–VLF approach enables the identification of vulnerable areas and supports the design of appropriate drainage and stabilization solutions.https://ijmge.ut.ac.ir/article_108686_3b64e27c9d196fb1caf81649e53290c8.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Machine learning-based methods to predict the tunnel water inflow: insights from the water conveyance tunnel database31332310868410.22059/ijmge.2026.400649.595291ENSasanGhorbaniDepartment of Mining Engineering, Hamedan University of Technology, Hamedan, Iran.0000-0002-7460-7900AliBameriDepartment of Mining Engineering, Isfahan University of Technology, Isfahan, Iran.Journal Article20250813Water inflow (WI) into the tunnel is one of the main geological hazards that can have a significant negative impact on the progress of the tunneling project. A precise prediction of the water inflow into the tunnel, as a significant challenge in rock tunneling, can guarantee project safety and progress. To address this, the current study applied five machine learning (ML) algorithms, including Random Forest (RF), Gradient Boosting (GB), Extreme Gradient Boosting (XGBoost), Categorical Boosting (CatBoost), and Natural Gradient Boosting (NGBoost). Therefore, a dataset including hydraulic conductivity (K), geological strength index (GSI), and water head (H) from 73 sections across six water conveyance tunnels in Iran was collected. The ML algorithms were implemented and then three performance metrics, including the coefficient of determination (R2), normalized root mean square error (NRMSE), and the variance account for (VAF) were employed to evaluate the efficiency of the ML models. As a result, the XGBoost model for testing data showed the greatest level of accuracy and reliability in predicting WI with R2, NRMSE, and VAF of 84.9%, 12.9%, and 82%, respectively. Also, based on the results of score analysis and regression error characteristic curve (REC), XGBoost was suggested as the best method for predicting WI in the tunnel. Finally, the water head was found to be the most effective parameter in predicting WI using the Shapley Additive exPlanations (SHAP) and Partial Dependence Plot (PDP) methods.https://ijmge.ut.ac.ir/article_108684_71d3cfe84fc8b019f8e1f1d681bfef24.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Numerical approach for designing support systems for underground excavations in serpentinite under squeezing ground conditions: the case of the Bou-Azzer mine, morocco32533510869710.22059/ijmge.2026.404369.595325ENAnasDriouchLaboratory of Applied Geophysics, Geotechnics, Engineering Geology and Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.0000-0003-1292-4692RedouaneOubahLaboratory of Applied Geophysics, Geotechnics, Engineering Geology and Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.0009-0005-0891-6886MohamedBhilisseFaculty of Sciences Semlalia, Cadi Ayyad University in Marrakech, Morocco.0009-0009-5845-6311AbdelazizLahmiliLaboratory of Applied Geophysics, Geotechnics, Engineering Geology and Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.LatifaOuadifLaboratory of Applied Geophysics, Geotechnics, Engineering Geology and Environment, Mohammadia School of Engineers, Mohammed V University in Rabat, Morocco.0000-0002-4613-1124Journal Article20251016The instability of underground excavations developed in serpentinite rock masses at the Bou-Azzer cobalt mine in Morocco has long been a critical concern for geotechnical engineering. The challenges encountered in two previous strategic projects, at depths of 360 meters and 510 meters, were mainly attributed to stress conditions exceeding the rock strength, leading to significant reductions in the cross-sectional area of the excavations and severe deformation of the installed support systems. Conventional empirical support design approaches applied at the mine have shown clear limitations when dealing with serpentinite rock masses. Another limitation of these methods is that they do not allow for the assessment of support system performance and deformation control to improve the stability of such deep excavations. The primary objective of this study is to develop a reliable support system capable of ensuring a safe working environment for personnel and equipment through numerical modeling of excavation behavior at a depth of 540 meters, corresponding to the new mine extension. The adopted methodology is based on detailed two-dimensional finite element modeling, explicitly accounting for the variability in the mechanical behavior of the serpentinite rock mass and its interaction with the proposed support systems through a site-specific analysis. Numerical simulations were conducted for different serpentinite types under two analysis scenarios: excavations during development and excavations with installed support. The results indicate that maximum displacements are critically high in type 4 serpentinite and remain substantial in type 1 serpentinite. By contrast, moderate displacement values were observed in type 2 and type 3 serpentinites. However, once the proposed support measures were implemented, the maximum displacements were reduced to acceptable limits with respect to the excavation span and height, and the safety factors improved to between 1.10 and 1.30 for the crown and from 1.10 to 1.60 for the sidewall. Numerical modeling has proven to be an effective decision-support tool for deep underground excavations in complex rock conditions. The findings of this study provide a practical and reliable basis for designing support systems in deep mining environments, with approaches that can be extended to other sites facing similar geotechnical challenges.https://ijmge.ut.ac.ir/article_108697_73061f5dcdf6915bc525d5b74d61ce56.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Advanced stability evaluation of underground marble quarry: a modelling and monitoring approach33734610897110.22059/ijmge.2026.407278.595342ENMritunjayKumarDepartment of Mining Engineering, NITK Surathkal, India.0009-0003-7490-9719AkhilAvcharDepartment of Mining Engineering, NITK Surathkal, India.ShambhaviSinhaDepartment of Mining Engineering, NITK Surathkal, India.Journal Article20251210This study evaluated the short-to-medium term static geomechanical stability of an underground marble quarry near Gujarat, India, using an integrated geomechanical approach combining FLAC3D numerical modeling, real-time in-situ stress monitoring, and empirical methods. The room-and-pillar system in a high-strength marble rock mass (GSI=72) intersected by a dolerite dyke was analyzed across varying overburden depths (57–87 m). Modeling confirmed pillar stability with stresses of 4.15–6.87 MPa and FOS consistently above 2.0. A 2-m-thick roof layer showed localized yielding, effectively controlled by 3.5-m-long, fully grouted Fe500D rockbolts (24 mm diameter, 2.2 m×2.2 m spacing), achieving FOS of 2.27–3.93 (resin grout: 3.93). In-situ monitoring recorded stress variations of 0.2–0.4 MPa, validating predictions and enabling back-analysis that refined the deformation modulus to 35 GPa for fractured marble. Monte Carlo simulations yielded a mean pillar FOS of 2.93 (95% CI: [2.21, 3.76]), with only 0.6% probability of FOS<2.0. The validated framework confirms short-to-medium term static geomechanical stability consistent with DGMS safety requirements, supports adaptive staged excavations near the dyke, and provides a replicable model for sustainable underground dimensional stone quarrying in complex geological settings.https://ijmge.ut.ac.ir/article_108971_08e8c9806b4cb262cbe0b32fc1e3ec23.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Euler deconvolution of a localized secondary fault of toru segment: the Batu Jomba landslide-prone road corridor34735610899310.22059/ijmge.2026.408790.595349ENNadiyahAz ZuhriyyahDepartment of Physics, Universitas Islam Negeri Sumatera Utara, Indonesia.0009-0009-2172-1847Lailatul HusnaLubisDepartment of Physics, Universitas Islam Negeri Sumatera Utara, Indonesia.0000-0002-4197-6494Rahmat NawiSiregarDepartment of Physics, Institut Teknologi Sumatera, Indonesia.0000-0001-5448-896XRussellOngDepartment of Physics, Univeristas Islam Negeri Sumatera Utara, Indonesia.0000-0002-6513-7046Journal Article20251226Landslide mitigation in active tectonic regions is a critical component of geo-environmental risk management, particularly in areas with steep topography near active fault zones. This study applies the Euler deconvolution formula on gravity data to delineate the presence of a localized secondary fault associated with the Toru Segment (a part of the Sumatran Fault Zone), within the landslide-prone road corridor in Batu Jomba. Previous studies in this area have primarily focused on fault slip rates and shallow-depth fault mapping, therefore, the detection of secondary fault activity intersecting the Toru Segment has not been explored. To address this gap, high-resolution gravity anomaly data from the GGMplus model (~200 m resolution) were processed using geophysical inversion to image subsurface density variations and Euler deconvolution formula was applied to estimate the depth of these two areas. The Batu Jomba area is characterized by a low Bouguer density of 2.0454 g/cm³, consistent with the Sihapas Formation dominated by weak sandstone lithology. Field observations corroborate the presence of sandstone boulders within the landslide body, indicating low material strength. Euler deconvolution results reveal the absence of direct structural expression beneath the Batu Jomba. However, clustered depth solutions in areas surrounding Batu Jomba delineate the presence of localized secondary fault at depths of 193-530 m, nearby the main Toru Segment. Regional Euler depth patterns indicate tectonic activity at depths of 193-590 m in part of the Toru Segment and 193-1,082 m in the Angkola Segment. The shallower depth extent of the Toru Segment and Batu Jomba area when compared to the Angkola Segment supports the interpretation of localized crustal thinning in the Toru Segment region at shallow depths. These findings indicate that the Batu Jomba landslide-prone road corridor is controlled primarily by weak lithology and the nearby presence of secondary fault rather than the main Toru Segment. The results highlight the effectiveness of gravimetric methods, particularly Euler deconvolution in characterizing fault activity and geo-hazard assessment, offering practical implications for engineering planning and disaster-risk reduction.https://ijmge.ut.ac.ir/article_108993_f8e0d4116572982b45d888957fe1dbb4.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Mapping hydrothermal alteration and gold mineralization in west Ahar using ASTER and Landsat 735736510897510.22059/ijmge.2026.410907.595358ENMajidShahhosseiniDepartment of Mining Engineering, Arak University of Technology, Arak, Iran.0000-0002-3030-369XFaramarzDoulati ArdejaniSchool of Mining, College of Engineering, University of Tehran, Tehran, Iran.0000-0002-4951-8850Journal Article20260210In this study, the capability of ASTER and Landsat 7 ETM+ sensors for alteration mapping at a scale of 1:20,000 and gold mineralization exploration in western Ahar, East Azerbaijan Province, Iran, was evaluated. The study area is composed of pyroclastic rocks, red to purple conglomerates, sandstones, and argillaceous limestones. The pyroclastic units, which host the gold mineralization zone, consist of alternating lapilli tuff, crystal–vitric tuff, lithic tuff, and volcanic rocks such as basaltic–andesitic lavas. To discriminate alteration zones and lithological units, advanced image processing techniques including band ratios, Principal Component Analysis (PCA), and Spectral Angle Mapper (SAM) were applied to the visible and near-infrared (VNIR) and shortwave infrared (SWIR) bands of the ASTER data. Band ratio techniques were also employed for processing Landsat 7 ETM+ data. The remote sensing results were validated through field investigations, petrographic studies, and geochemical analysis of gold. In the ASTER imagery, false color composites (4–6–8 and 7–2–9) effectively discriminated argillic–sericitic alteration, while the band ratio (14/12) optimally enhanced silicic alteration. In the Landsat 7 imagery, the false color composite RGB = B3/B1 – B3/B5 – B5/B7 was suitable for lithological discrimination, and the band ratio (1/3) effectively highlighted iron oxide alteration. The results confirm the effectiveness of the applied image processing methods in alteration mapping and identifying mineralization potentials, with gold grades ranging from 0.021 to 3.128 g/t in the study area.https://ijmge.ut.ac.ir/article_108975_c5798b8e6080bd39192cc3fc59afb516.pdfUniversity of TehranInternational Journal of Mining and Geo-Engineering2345-693060320260901Effects of ore types and blending strategy on the flotation performance, using igneous phosphate ore from Esfordi deposit36737710906010.22059/ijmge.2026.419137.595411ENMohammadDehghaniSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran.HassanMalekiSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran.0000-0003-3103-3334YasamanzahraAlishahihaSchool of Mining Engineering, College of Engineering, University of Tehran.MohammadNoaparastSchool of Mining Engineering, College of Engineering, University of Tehran.0000-0002-8688-4593GolnazJozanikohanSchool of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.0000-0002-5920-0424Journal Article20260722The Esfordi deposit, Iran's largest igneous phosphate resource, exhibits significant mineralogical heterogeneity that causes feed quality fluctuations and compromised flotation performance. This study presents the first systematic comparison of two mineralogically distinct ore types from this deposit: an iron-rich apatite ore (P1) and a clay-bearing green phosphate ore (P2). Feed blending was then evaluated as a practical strategy for managing this ore variability. Mineralogical characterization revealed that P1 contained 13.86% P₂O₅ and 47.17% Fe₂O₃, whereas P2 assayed 10.72% P₂O₅ and 16.55% Fe₂O₃ and contained 10.6% clay minerals. Flotation conditions were optimized through systematic studies of collector dosage, pH, starch dosage, and cleaning stages following desliming. Under optimized conditions (pH 9.5 and 400 g/t starch), P1 achieved a concentrate grade of 40.81% P₂O₅ and 80.53% recovery, using only 280 g/t collector—down from the current plant practice of 680 g/t, a 59% reduction. In contrast, P2 required 680 g/t collector and yielded 31.05% P₂O₅ with 71.38% recovery, due to increased reagent consumption associated with clay minerals. Among the tested blending ratios, the 70:30 (P1:P2) blend provided the most favorable balance, producing a concentrate containing 35.26% P₂O₅ and 2.08% Fe₂O₃ with 63.82% recovery while reducing collector consumption by 32% relative to P2 alone. These findings demonstrated that feed blending can effectively mitigate the adverse effects of ore type, maintain concentrate quality, and reduce reagent requirements. Adjusting blending ratios and reagent dosage according to feed characteristics can improve flotation performance and provide practical guidance for plant operation.https://ijmge.ut.ac.ir/article_109060_cc652cbd7322c252dc18d5d510740f9e.pdf