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We present the results of an investigation for REE, carried out on the Silius fluorite vein system (SE Sardinia, Italy), which is similar to other late- to post-Hercynian mineralizations of this type in Europe. The mineralogical study evidenced that REE-fluorocarbonates, mainly represented by synchysite, occur in the gangue of the vein system, in association with hydrothermal dolomite and quartz. This is a relevant discovery, because this mineral association has been commonly observed in several fluorite vein systems genetically related to magmatic activity, whereas it is rare in non-magmatically associated hydrothermal veins.

Supergene Zn(Pb)-nonsulfide deposits consist mainly of Zn/Pb-carbonates (smithsonite, hydrozincite, cerussite), Zn-(hydro)silicates (hemimorphite, sauconite), Fe-hydroxides, minor Fe-Pb-sulfates (i.e. anglesite, jarosite) and Zn-Pb-phosphates (i.e. tarbuttite, pyromorphite), commonly associated with remnants of primary sulfides (sphalerite and galena), which form from oxidation of sulfide-bearing concentrations by meteoric waters. The relative abundances of these mineral phases and the mineral species precipitating are strongly dependent on the type of host rock. Their variable mineralogy is complex to characterize, and it is crucial to define the processing method and foresee the metal recovery. Since most nonsulfide Zn-Pb deposits are amenable to be treated by hydrometallurgy, e.g. by leach/solvent extraction/electrowinning, AmmLeach®, etc., an incorrect evaluation of the modal distribution, or of the relations between ore and gangue minerals could lead to a severe increase of the production costs or drive the choice of the processing route in erroneous directions. Objective of this thesis, hence, was to integrate the more traditional analytical technologies (OM, CL, SEM-EDS, WDS and CA) with the "Automated Mineralogy" analysis system (QEMSCAN®), in order to improve the accuracy of nonsulfide ores characterization. Part of this aim has been reached by the comparison of the quantitative evaluation of three nonsulfide deposits, carried out with two different methods: XRD-quantitative (i.e. Rietveld) and QEMSCAN®. As a conclusion, it was possible to discuss the advantages and limitations of both methods, for the choice of the best routine during feasibility study. Three supergene nonsulfide zinc deposit with different grades of mineralogical complexity have been considered for this purpose: Hakkari Zn(Pb) in Turkey; Jabali Zn-Pb(Ag) in Yemen; Reef Ridge Zn in Alaska. The general geology, mineralogy and geochemistry of each of these deposits have been evaluated separately, either from already known reference literature, or on the base of recently obtained scientific results. These data are considered preliminary to the QEMSCAN® analyses, and should be assimilated during the evaluation through Automated Mineralogy. The Hakkari zinc deposit is located in the extreme southeastern region of Turkey, approximately 10 km west of the town of Hakkari, within a broad 20 km wide and 100 km long east-west belt. The orebodies, consisting of both sulfide and nonsulfide Zn≫Pb ores occur in Middle-Triassic to Early Cretaceous shallow water carbonate rocks within the northern margin of the Arabian Platform. The nonsulfide ore, which represent the most economic portion of the deposit, consists of overall estimated compliant resources of at least 10 Mt @ 15% Zn. Traditional techniques were used to carry out a complete geochemical, petrographic and mineralogic characterization of the Hakkari economic ore. This mineral association typically comprises smithsonite and hemimorphite, which apparently replace both sulfide minerals and carbonate host rock. Two generations of smithsonite occur: the first is relatively massive, the second occurs as concretions in cavities. Some zinc is also hosted within Fe–Mn-(hydr)oxides. Lead is present in cerussite, but also in Mn-(hydr)oxides. In the whole mineralized area a diffuse As-Sb-Tl geochemical enrichment also occurs. Silver is also present locally. The features of the supergene mineralization suggest that the Hakkari deposit belongs both to the "direct replacement" and "wall rock replacement" after the Hitzman et al. (2003) classification. Carbon-oxygen stable isotopes geochemistry has been carried out on the nonsulfide minerals (smithsonite), in order to define the nature of the mineralizing fluids and the genesis of the mineralization. The δ13C values range from -3.3‰ to -6.0 ‰ VPDB. These values are comprised in the characteristic δ13C interval of supergene smithsonites, and are interpreted as a result of mixing between carbonate carbon from the host rock and soil/atmospheric CO2. The δ18O values of smithsonite lie between 24.2 ‰ and 25.3 ‰ VSMOW: these values can be associated with a smithsonite deposition from supergene weathering fluids of possible Upper Tertiary age. The Hakkari samples were also analyzed quantitatively both by the XRD-Rietveld and QEMSCAN® methods. QEMSCAN® analysis also allowed a more detailed mineralogical characterization of several Hakkari drill cores. The study with the "Automated Mineralogy" technique confirmed the main mineral phases (smithsonite and hemimorphite) recorded with traditional methods, but identified other phases not previously detected (e.g. minerals in trace amounts such as sauconite), being also able to distinguish and quantify impure phases (e.g. Zn-dolomite, Cd-calcite), and identify amorphous phases [pyrite/Fe-(hydr)oxides/jarosite mix] that XRD had found challenging. In particular, the modal mineralogy of the ore and gangue minerals, the mineral association and the spatial distribution data of the economic minerals at Hakkari provided information for the advanced exploration phase of the deposit. Jabali is a Zn-Pb-(Ag) nonsulfide deposit, located 110 km northeast of Sana'a, the capital of Yemen along the western border of the Marib-Al-Jawf/Sab'atayn basin. The deposit covers an area of about 2 km2. The orebody is hosted in the Jurassic carbonate rocks of the Shuqra Fm. (Amran Gp.). It is is almost completely oxidized with only a small portion unaltered thanks to an impermeable sediment cover. Ore characterization by the use of traditional analytical techniques revealed that smithsonite is the main zinc mineral, while hemimorphite and hydrozincite are less common. Cerussite and anglesite also occur as main lead minerals. Goethite, hematite, and Mn-(hydr)oxides are common throughout the mining area. Ag-sulfide and native silver are also present locally. Zn-enriched dolomite was detected by the use of SEM-EDS analyses in many samples from several zones of deposit, even if not quantified by XRD-Rietveld analyses. The δ13C values of smithsonite vary from -2.9‰ and 5.7‰ VPDB. The δ18O values range from 19.0‰ to 21.4‰ VSMOW. The δ13C values are in the range of supergene smithsonites worldwide and point to a mixed source of carbon (organic matter in the soil, atmospheric CO2, and host rocks). The δ18O values, instead, indicate the effects of temperature-related fractionation along the cores. This is probably due to variable precipitation temperatures of the Zn-carbonate; a hydrothermal component cannot be excluded. Several hypotheses have been formulated on the age and genesis of the supergene mineralization. Some authors propose a long period of oxidation, subdivided in several phases, extended from Cretaceous to Present, whereas others believe that there has been a single oxidation stage, which started in Miocene and continues until Present. A renewed mineralogical characterization and quantitative evaluation of the Jabali deposit was carried out by the use of QEMSCAN® automated technology and proposed as one of the main subject of this thesis. The main aim was the improvement of the knowledge of mineral association and element deportment for the Jabali supergene ore. The results confirmed the main findings of the previous studies and added new and more detailed information: smithsonite is mostly associated and intergrown with Fe-(hydr)oxides and remnants of primary sulfides; the host dolomite is locally replaced by broad bands of Zn-rich dolomite (which has been quantified by QEMSCAN®), where Zn has substituted for Mg. Hemimorphite, cerussite and anglesite occur in minor amounts (in agreement with previous studies). The Ag-sulfides are mainly associated with anglesite. Gypsum, Fe-(hydr)oxides (goethite>hematite), Zn-Mn-(hydr)oxides and Pb-Mn-(hydr)oxides have been detected locally. The QEMSCAN® technique, hence, combined with data previously obtained from other analytical techniques (XRD, SEM-EDS, optical petrography), has provided detailed mineralogical and textural information on the Jabali mineralization. A key outcome from this QEMSCAN® study is the textural data and quantification of the Zn-dolomite, and this was an important result, because the occurrence of abundant Zn-dolomite in the host rock caused issues in the recovery steps during the choice of the best processing route. The combination of techniques used to examine the Jabali supergene ore provides high quality information that not only characterizes the deposit in detail, but also offers a better understanding for the design of ore processing options and a more realistic predicted recovery of economic minerals. The Reef Ridge prospect is a typical supergene nonsulfide zinc mineralization, located in the Yukon-Koyukuk region of west central Alaska (USA). It is hosted in sedimentary rocks of the Farewell Terrane, a continental fragment sandwiched between the Siberian and Laurentian cratons during the early Paleozoic. The mineralization occurs in Lower-Middle Devonian dolomites belonging to a Paleozoic carbonate platform succession. The mineralization consists of oxidized minerals, associated with minor sulfide remnants. The results of a complete petrographic and mineralogical study (XRD, chemical analysis, SEM-EDS and QEMSCAN®) show that Reef Ridge has a simple mineralogy compared to the Hakkari and Jabali deposits. The most abundant mineral in the nonsulfide ore is smithsonite. Similar to other nonsulfide zinc deposits worldwide, a first generation of smithsonite, has replaced both primary sphalerite and the host carbonates. A second smithsonite generation precipitated as cement in vugs and fractures. Minor zinc amounts also occur in the Fe-(hydr)oxides and zinc traces have been identified in clay minerals. Geochemical isotope analyses have been carried out on the carbonate minerals, in order to define the genesis of the supergene ore. Carbon and oxygen isotope values of smithsonite at Reef Ridge range from -0.7 to 2.1‰ VPDB and 19.1 to 21.9‰VSMOW, respectively. The δ13C values suggest that the predominant carbon source for smithsonite were the host carbonates, with a limited contribution from organic carbon. The oxygen isotope ratios are much more depleted in 18O compared to supergene nonsulfides from other parts of the world, formed under warm-humid, temperate or semi-arid climates. The depletion in 18O of precipitating waters, indicate that the formation of the Reef Ridge nonsulfide deposit is probably related to cold/humid weathering episodes during late Tertiary to Recent. These findings have subverted the "traditional" theory that the supergene Zn nonsulfide deposits only form in warm-humid, temperate or semi-arid conditions. As the other two analyzed deposits, also Reef Ridge shows the features of both "direct replacement" and "wall rock replacement" supergene ores. Although the considered deposits represent three typical examples of supergene nonsulfide Zn-(Pb) ore concentrations, their study has revealed several important mineralogical and petrographic differences: Jabali resulted to be the most mineralogically complex of the three, due to the number of occurring mineral phases (smithsonite, Fe-(hydr)oxides, cerussite, anglesite, remnants of sphalerite and galena, and several other minor phases, i.e. Ag-minerals, sauconite, kaolinite, gypsum, calcite) and because of the local occurrence of high amounts of Zn-(Pb) in several mineral phases (i.e. Zn-dolomite). The mineralogy of the Hakkari deposit is also not quite straightforward, with zinc occurring mainly as smithsonite and hemimorphite, lead as cerussite and anglesite, associated with Fe- and Mn-(hydr)oxides. The mineralogy of the Alaskan deposit, instead, is quite simple, because it consists of smithsonite, with some Fe-(hydr)oxides and rare sphalerite. The study of these three deposits was carried out with the use of several traditional techniques, and a more recent analytical technique (QEMSCAN®) to better comprehend the feature of the deposits mineralization. During the analyses we faced with several issues that sometimes resulted in unaccurate information and misleading data: e.g. the occurrence of unidentified amorphous phases, the absence of phases wrongly determined earlier (i.e. ankerite and Zn-ankerite), the occurrence of not quantificable mixed phases, and the difficulty to characterize a few mixed mineral compounds. To overcome this problem, was necessary the support of several analytical techniques, and the comparison of the results obtained with each of them. The main conclusion of this study is that the characterization of nonsulfide Zn-deposit, and especially their quantitative evaluation (QPA) may be quite tricky, because of their complex mineralogy. The lack of accurate mineralogical results can cause several problems in the processing and metallurgical stages (recovery issues, penalties at the smelter, poor metal quality, and environmental damage). QEMSCAN® is an useful tool for ore characterization during exploration and potential processing steps, as it can provide detailed information on the texture, add significant information on the major and trace mineral distribution, and produce a good quantitative evaluation of the isomorphic phases that typically characterize the minerals occurring in nonsulfide deposits. However, even though there are many positive aspects in applying this technique, it is important to remark that the QEMSCAN® data cannot be used alone, because of some ambiguity in minerals identification.

Bauxites in southern France (Provence and Languedoc) have been exploited since the beginning of the last century. Though most of the deposits are now subeconomic or mined-out, these bauxites represent model analogs for other economic bauxites of the world. These Cretaceous karst-type deposits lie directly on Jurassic carbonates, and have been formed through a combination of different processes: in-situ alteration of siliciclastic sediments deposited on carbonate platforms, and reworking of early bauxites in the karst network. In this study, we present preliminary bulk rock geochemical and in-situ laser ablation (LA) -ICP-MS analyses on Al- and Fe-oxy-hydroxides of Provence (Les Baux-de-Provence) and Languedoc (Villeveyrac, Loupian) bauxites, with the aim of evaluating the concentrations of rare earth elements (REEs) and their deportment in these minerals. REEs have total average concentrations of 700 mg/kg in the analyzed samples, which are mostly composed of boehmite, γ-AlO(OH), and Fe-oxy-hydroxides (hematite and goethite). Maximum REEs concentrations are commonly associated with positive Ce anomalies in chondrite-normalized patterns. In contrast with other examples from the literature, it has been observed that high REE concentrations also occur in samples apparently devoid or poor of REE-minerals. In these samples, the total amount of REEs is positively correlated with that of Ga (commonly contained in boehmite). LA-ICP-MS trace element analyses on boehmite and Fe-oxy-hydroxides have shown that while the Al-hydroxide contains the suite of REEs, goethite and hematite are preferentially enriched only in Ce. Considering that Al-hydroxides are digested during the Bayer process, an interesting issue to develop in the future is whether (and how) REEs released during Al-hydroxide digestion could be recovered together with Al from the pregnant leach liquor, as routinely done for Ga., Minerals, 9 (9)

This chapter offers an overview of Scanning Electron Microscopy (SEM) and Electron Microanalysis fundamentals using Energy Dispersive Spectroscopy (EDS) and Wavelength Dispersive Spectroscopy (WDS). The main technical features and steps necessary to acquire high-resolution images and obtain reliable chemical analytical results are here briefy summarized. The chapter also describes the main advantages of using this non-destructive technique for forensic geosciences applications, with a particular focus on Automated Mineralogy (AM). This analytical technique expands the potentiality of modern SEM systems, allowing a rapid achievement of mineral classifcation and modal composition of grain mixtures. Finally, we present real case studies on applying SEM-EDS, WDS, and AM techniques to several felds of forensic geology. Signifcant examples will include studies on prediction of soil provenance, fngerprinting of airborne asbestos, and comparison between soils and sediment samples to test an association between a soil residue found at a crime scene and relevant items for investigation.

The Silius vein system, located in SE Sardinia (Italy) is analogous to other late- to post-Hercynianmineral systems of this type in Europe. The Silius system consists of two main veins, characterized by several generations of fluorite, calcite and quartz,with initial ribbon-like geometries, followed by breccias and cockade-like textures. In this study, aimed at investigating the REE concentrations in the Silius vein system, a REE average of ~800 ppm(locally ΣREE N1500 ppm) has been observed in the carbonate gangue of the fluorite orebody. These amounts are related to the presence of the REE-bearing minerals synchysite-(Ce) and xenotime-(Y). The chemical composition of synchysite-(Ce) has been obtained by wavelength dispersive spectrometry (WDS). The average synchysite- (Ce) formula, built on the basis of (CO3)2F and 5 negative charges, is Ca1.07(La0.19,Ce0.36,Pr0.04,Nd0.15, Sm0.03,Gd0.03,Y0.13)(CO3)2F. From their geochemical characteristics, and their textural relationships with other gangue phases, it is likely that synchysite-(Ce) and xenotime-(Y) formed at the same P-T-X conditions as the other minerals of the Silius fluorite mineralization. Synchysite-(Ce) and xenotime-(Y) at Silius could be related to a local circulation phenomenon, where the REE are derived from a REE-bearing source rock in the basement of southeastern Sardinia,which has been leached by the same fluids precipitating the fluorite/calcite mineralization. REE concentrations contained in the carbonate gangue of still unexploited parts of the Silius vein deposit, as well as in dumps and tailings accumulated during past fluorite processing, could possibly represent a sub-economic by-product of the fluorite exploitation.

The Reef Ridge deposit is a typical supergene “nonsulfide” zinc mineralization, located in the Yukon-Koyukuk region of west-central Alaska (USA). It is hosted in sedimentary rocks of the Farewell terrane, a continental fragment sandwiched between the Siberian and Laurentian cratons during the early Paleozoic. The mineralization occurs in Lower–Middle Devonian shallow-water dolomite of a Paleozoic carbonate platform succession belonging to the Nixon Fork tectonic unit. The mineralization consists of oxidized minerals associated with minor remaining sulfides (pyrite/marcasite and sphalerite). In the oxidation zone, smithsonite is the predominant mineral, mixed with Fe-(hydr)oxides (goethite and hematite). A complete petrographic and mineralogical study was performed. Samples were analyzed by X-ray diffraction, inductively coupled plasma–mass spectrometry and emission spectrometry, energy dispersive scanning electron microscopy, and QEMSCAN ® (quantitative evaluation of minerals by scanning electron microscopy). The most abundant mineral in the nonsulfide ore is smithsonite. Similar to other nonsulfide Zn deposits worldwide, the first generation of smithsonite has replaced both primary sphalerite and the host carbonates. A second smithsonite generation precipitated as cement in vugs, cavities, and fractures. Minor zinc amounts also occur in the Fe-(hydr)oxides, and zinc traces have been identified in clay minerals. The carbon and oxygen isotope values of smithsonite at Reef Ridge vary from −0.7 to 2.1‰ relative to Vienna Peedee belemnite (VPDB) and 19.1‰ to 21.9‰ relative to Vienna standard mean ocean water (VSMOW). The δ 13 C values are similar to those of the host rock, suggesting that the predominant carbon source for smithsonite was the host carbonates, with only a limited contribution from organic carbon. The oxygen isotope ratios of Reef Ridge smithsonite are more depleted in 18 O compared to supergene nonsulfides from other parts of the world formed under warm-humid, temperate, or semiarid climates. The oxygen isotope fractionation between water and smithsonite, which relates the δ 18 O value of the mineralizing solution, the formation temperature of smithsonite, and its δ 18 O composition, indicates that the δ 18 O composition of Reef Ridge smithsonite is related to very low formation temperatures (~10 °C), and strong depletion in 18 O of the precipitating waters. The δ 18 O smithsonite composition, the strong 18 O depletion, and the relationship of the formation of the Reef Ridge nonsulfide deposit with the development of the Sleetmute upland surface (which started in the Late Tertiary and continues to the present) indicate that the formation of the Reef Ridge nonsulfide deposit is probably related to cold/humid weathering episodes during a period comprised between Late Tertiary and Holocene. The “traditional” interpretation on the genesis of Zn nonsulfide deposits in warm-humid, temperate, or semiarid conditions should be questioned where other climate zones are indicated.

The development of relatively simple and low-cost processing technologies such as solvent-extraction, AmmLeach®, leach/solvent extraction/electrowinning and pyrometallurgy, combined with the increase in Zn prices, resulted in an increase in the study and exploration of nonsulfide Zn(Pb) deposits. The Hakkari deposit is an example of a supergene nonsulfide Zn(Pb) deposit located in Southeast Turkey, hosted in brecciated Jurassic limestone. The ore concentrations, mainly consisting of oxidized Zn minerals (smithsonite and hemimorphite) were examined in this study using QEMSCAN®. The formulation of a Species Identification File (SIP) was necessary to discriminate the mineral species. QEMSCAN® analysis allowed detailed mineralogical characterization of several Hakkari drill core samples, building on, and adding to previous studies of the deposit. In particular, the modal mineralogy for the ore and gangue minerals, and mineral association and spatial distribution data of the economic minerals provided information for the advanced exploration phase of the deposit, which could influence the feasibility study and ore processing options. The results show that smithsonite is the main ore mineral, occurring in two generations: one (FeO and PbO bearing) replaces sphalerite and host carbonates, and another (CaO-bearing) is concretionary in cavities. Hemimorphite occurs in cavities or replaces smithsonite in veinlets. Fe-(hydr)oxides can be enriched in Zn, Pb, As and SiO 2 . Mn–Fe-(hydr)oxides (Pb ≫ Zn enriched) are rare. Remnant sulfides have also been detected. The QEMSCAN® study has confirmed the main mineral phases found in previous studies, but identified other phases not previously detected (e.g. minerals in trace amounts such as sauconite), being also able to distinguish and quantify impure phases (e.g. Zn-dolomite, Cd-calcite), and identify amorphous phases [pyrite/Fe-(hydr)oxides/jarosite mix] that XRD found challenging. Not detecting the detrimental minerals/elements may result in processing problems, penalties at the smelter, poor metal quality, and environmental damage. Thus the use of QEMSCAN® technology on this type of deposit is beneficial for both exploration and potential processing, provided that careful attention is paid to the complex mineralogy and limitation of the analysis technique.

The southern Italian karst bauxite deposits occur at a Late Cretaceous hiatus on a Bahamian-type carbonate platform succession cropping out in the southern Apennines, and are mainly located in the Abruzzi Mountains, in Apulia (Gargano peninsula and Murge area), and in Campania. The bauxites of southern Italy are presently uneconomic, but can be considered as a model analogue for economic karst bauxite ores. The texture of the bauxite deposits is mainly oolitic to pisolitic but can also be arenitic-conglomeratic, suggesting reworking of evolved lateritic soils. The minerals boehmite and hematite are more abundant in the ooids, whereas kaolinite is found at high levels in the groundmass, and titanium oxides are also present. Furthermore, small amounts of rare earth elements have been detected in most of the bauxite occurrences. Scanning electron microscopy with energy dispersive spectrometry (SEM-EDS) and geochemical analyses on several of the deposits confirmed the diagenetic texture of the bauxite, and provided an estimate of the mineralogy of the different components and their chemical composition. The mineralogical and petrographic characteristics of bauxite are crucial for the Bayer process and can influence its economic evaluation: both the particle size distribution in the ore and the presence of reactive silica phases associated with Ti and Fe oxides can reduce the efficiency of processing. Quantitative analyses combining different methods (X-ray diffraction [XRD]-Rietveld quantitative phase analysis [QPA] and QEMSCAN ® ) have been carried out on a limited number of samples from two of the bauxite districts of the Campania region: the Matese Mountains and the Caserta province. QEMSCAN ® analysis allowed a more rapid quantification of mineralogy (including trace detrital phases) and assessment of the individual textural characteristics of the bauxite lithotypes, showing a detailed image of the distribution of economic and noneconomic minerals and their intergrowths. This methodology can augment or replace other time-consuming quantitative phase analyses for mineralogical studies of bauxites, provided that the species identification protocol (SIP) database has been carefully validated by preliminary use of XRD and SEM-EDS. Both XRD (QPA) and QEMSCAN ® analytical techniques can be complementary for bauxite ore evaluation, and a very powerful tool for exploitation and mineral processing.

Supergene nonsulfide Zn-Pb deposits consist mainly of Zn-Pb carbonates, Zn silicates, Fe hydroxides, and minor Zn-Pb phosphates, commonly associated with remnants of primary sulfides (sphalerite and galena). The relative abundances of these mineral phases are strongly dependent on the type of host rock. Their variable mineralogy is complex to characterize, and can lead to problems during the processing and recovery of the minerals from the ores. In this case study, mineralogical characterization and quantitative evaluation of the Jabali (Yemen) nonsulfide Zn-Pb deposit was carried out using automated scanning electron microscopy (QEMSCAN®). Both primary and secondary ores at Jabali are hosted in Jurassic dolostones. Smithsonite is the most abundant economic ore mineral in the supergene deposit, and it is locally intergrown with Fe hydroxides and remnants of primary sulfides (sphalerite and galena). The host dolomite is locally replaced by broad bands of Zn-rich dolomite, where Zn has substituted for Mg. The ZnO content in this dolomite can reach 22 wt %. Other Zn minerals such as hemimorphite and hydrozincite occur in limited amounts, as well as cerussite and anglesite. Small particles of Ag sulfide are associated with the secondary minerals. Gypsum, Fe (hydr)oxides (goethite > hematite), Zn-Mn (hydr)oxides, and Pb-Mn (hydr)oxides have been detected locally. The QEMSCAN technique, combined with data previously obtained from other analytical techniques (X-ray diffraction [XRD]), scanning electron microscope-energy dispersive spectrometry [SEM-EDS], optical petrography), has provided detailed mineralogical and textural information on the Jabali mineralization. A key outcome from this QEMSCAN study is the textural data and quantification of the Zn dolomite, which is fairly abundant in this deposit. The combination of techniques used to examine the Jabali supergene ore provides high-quality information that not only characterizes the deposit in detail, but also offers a better understanding for the design of ore processing options and a more realistic predicted recovery of economic minerals.