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This, the fourth paper on Scottish Mineral GCR sites, deals with minerals produced during the late stages of granitic rocks creation. Five sites are described and interpreted, encompassing both minerals within intrusive rocks and those which formed in the adjacent country rocks. The former range from previously-mined, porphyry-style copper-molybdnum sulphide concentrations to one of the few Scottish occurrences of tungsten mineralization. Mineral deposits formed in mostly calcareous country rocks by the exchange of elements between granitic bodies and them are generally referred to as skarns. They are geographically more widespread than the within-granite bodies, and comprise calc-silicate minerals such as diopside, grossular garnet, wollastonite and, more rarely vesuvianite. In one instance, the skarns contain a wide range of mineral assemblages including some with boron fluoride minerals and mineable concentrations of iron ore. Probably the most enigmatic of these is an apparent exoskarn type assemblage but is devoid of an associated granite.

The Wujiaping Sn deposit is located at the northern Dayishan ore field, South China, whose ore veins are mainly hosted in the Dayishan pluton. LA–ICP–MS zircon U–Pb dating for the medium-fine grained- and medium-coarse grained-biotite monzogranite of Dayishan pluton yields emplacement ages of 154.5 ± 1.6 Ma (MSWD = 2.0) and 155.5 ± 0.5 Ma (MSWD = 1.9), respectively, which are consistent with the muscovite 40Ar-39Ar plateau age of 150.4 ± 0.9 Ma for the quartz vein type ore veins. It is indicated that the Sn mineralization in the Wujiaping deposit is related to the Late Jurassic granitic magmatism. These granites show the geochemical features of highly fractionated S-type granite: 1) low Zr + Nb + Ce + Y contents ( 1.1); 3) low crystallization temperature (mean = 688 °C); 4) high Rb/Sr ratios (mostly > 48); 5) high differentiation index (DI > 90); and 6) low CaO, P2O5, Sr, and Eu contents. Whole rocks isotopes show that these granites shows variable initial 87Sr/86Sr ratios (0.70251–0.71208), negative eNd(t) values (−7.94–5.62) and old two stage Nd model ages of 1491–1563 Ma. LA–MC–ICP–MS zircon Lu–Hf isotopes show that the medium-fine-grained monzogranite have positive eHf(t) values of 0.37–8.5 and two stage Hf model ages of 662–1180 Ma, whereas the medium-coarse grained-biotite monzogranite have negative eHf(t) values of −6.42–3.55 and two stage Hf model ages of 1431–1599 Ma. It is proposed of that these granites are originated from melts mixed by crustal- and mantle-constituents and are formed in an extensional setting caused by the subduction of the Palaeo-pacific plate. The low LogfO2 values calculated through zircons (−21.2–13.1) and high F contents (3630–5120 ppm) indicate the granites derived from reduced and F-rich melts. Therefore, the reduced melt is highly fractionated and enriched in Sn and F, resulting in the large scale Sn mineralization in the Dayishan ore field.

Discovering ore deposits is becoming increasingly difficult, and this is particularly true in areas of glaciated terrains. As a potential exploration tool for such terrains, we test the vectoring capacities of trace element and sulfur isotope characteristics of pyrite, combined with quantitative statistical methods of whole-rock geochemical datasets. Our target is the Rajapalot gold–cobalt project in northern Finland, where metamorphosed Paleoproterozoic volcanic and sedimentary rocks of the Peräpohja belt host recently discovered gold prospects, which also have significant cobalt enrichment. The focus is particularly put on a single gold–cobalt prospect, known as Raja, an excellent example of this unusual cobalt-enriched gold deposit, common in the metamorphosed terranes of northern Finland. The major lithologies at Rajapalot comprise amphibolite facies metamorphosed and polydeformed calcsilicate rocks that alternate with albitic units, mafic volcanic rocks, mica schist and quartzite. Mineralization at Rajapalot prospects is characterized by an older Co-mineralizing event and a younger high-grade Au mineralization with re-mobilization and re-deposition of Co. Detailed in situ laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a powerful technique that produces robust trace element and sulfur isotope databases from paragenetically and texturally well-characterized pyrite from the Raja prospect. The results are treated with appropriate log-ratio transformations and used for multivariate statistical data analysis, such as the computation of principal components. Application of these methods revealed that elements such as Co, Ni, Cu, Au, As, Ag, Mo, Bi, Te, Se, Sn, U, Tl and W have high vectoring capacities to discriminate between Co-only and Au–Co zones, as well as between mineralization stages. The systematic pyrite study suggests that homogenous sulfur isotopic characteristics (+1.3 ‰ to +5.9 ‰) and positive loadings of Co, Se, As, Te, Bi and Au onto PC1 are reflective of an early stage of Co mineralization, while the opposing negative loadings of Mo, Ni, W, Tl, Cu and Ag along PC1 are associated with pyrites from the Au-mineralizing event. The sulfur isotopic signature of the latter pyrite type is between −1.2 ‰ and +7.4 ‰. Subtle patterns recognized from the whole-rock geochemistry favor an As–Au–Se–Te–W–U signature along the positive axis of PC1 for the localization of high-grade Au–Co zones, whereas the element group Ni, Cu, Co, Te, Se and As, which has negative loadings onto PC2, will predict Co-only zones. This study shows the efficiency of trace element geochemistry in mineral exploration targeting, which has the capacity to define future targets by characterizing the metallogenic potential of a host rock, as well as distinguishing various stages of mineralization.

Haerdaban is a newly discovered Zn–Pb deposit (0.64 Mt at 6.19 wt% Zn and 1.09 wt% Pb) in the Western Tianshan, NW China. Sulfide mineralization mainly occurs as veins, breccias, and semi-massive ores within the dolomitic limestone and calcareous slate. Here we use Rb–Sr sphalerite and SHRIMP U–Pb zircon geochronology to place constraints on the age and formation of the deposit. Rb–Sr dating of sphalerite gives an isochron age of 432 ± 45 Ma (n = 6; 87Sr/86Sri = 0.7102 ± 0.0020), providing a direct age constraint for the main mineralization. SHRIMP U–Pb data for detrital zircon from three samples of host siliceous dolomite have relatively similar age modes with prominent age peaks at 1576 Ma, 1781 Ma, and 1848 Ma, and a smaller peak at 1375 Ma. The maximum depositional age for the host dolomite is constrained at 1099 ± 21 Ma by the weighted mean age of the four youngest detrital zircons. These results demonstrate that the main mineralization clearly postdates the host sedimentary rocks. Zircons from two diorite samples and one granite sample yield overlapping 206Pb/238U ages with a weighted mean of 394.5 ± 1.5 Ma. This age is slightly younger but within analytical uncertainty of the 432 ± 45 Ma for the ores, implying a possible temporal relationship between intrusions and main mineralization. The igneous intrusions could provide the heat to drive the hydrothermal system responsible for main-stage mineralization. Haerdaban is interpreted to be a metamorphosed SEDEX Zn–Pb deposit that has been remobilized by subsequent hydrothermal activity.

Late-stage metamorphic (ca. 2.64 Ga) and punctuated magmatic-hydrothermal mineralization models (2.67–2.64 Ga) are proposed for gold mineralization in the Kalgoorlie gold camp (~ 2300 t Au; Archean Yilgarn craton, Western Australia). We present structural, whole-rock geochemical, pyrite trace element, and multiple sulfur isotope data to evaluate these models. Both the Fimiston and Hidden Secret lodes were emplaced in ca. 2675 Ma D2b transtensional settings as releasing bends developed along the Golden Mile and Towns faults, respectively, and are related to the ingress of a H2O-CO2-Au-Te-As-S-K-Rb-Ba fluid concomitant with the intrusion of andesitic dikes. In the Hidden Secret orebody, this magmatic-hydrothermal fluid evolved from an early, As-enriched, greenstone-buffered fluid during the formation of disseminated pyrite mineralization (δ34Spyrite = 3.42 to 3.85‰; Δ33Spyrite = 0.25 to 0.43‰) to an Ag-Cu-Pb-Sb-Te-Tl-V-Zn–enriched fluid during the development of banded quartz-carbonate-sericite-pyrite veins (δ34Spyrite = - 10.74 to - 0.17‰; Δ33Spyrite = 0.06 to 0.19‰). Oroya gold-telluride lode mineralization formed during later, ca. 2660 Ma D2c transpression from a V-S–Au-Ag-Hg-Te–enriched magmatic-hydrothermal fluid represented by δ34Spyrite = - 11.56‰ to - 4.96 and Δ33Spyrite = 0.08 to 0.17‰. The Fimiston/Hidden Secret and Oroya mineralization events record oxidized magmatic-hydrothermal fluids represented by δ34Spyrite ≤ 0‰ and Δ33Spyrite ~ 0.0 to 0.2‰. These oxidized magmatic-hydrothermal fluids interacted with surrounding wall rock, which lowered fluid fO2 and buffered δ34Spyrite/Δ33Spyrite values to δ34Spyrite = ~ 1 to 5‰/Δ33Spyrite = ~ 0.2 to 0.7‰ in greenstone rock environments and to δ34Spyrite = ~ 1 to 5‰/Δ33Spyrite = ~ ≤ 0.3‰ and ≥ 0.7‰ in black shale environments. Anomalous Δ33S values in ore-stage sulfides formed locally due to the incorporation of sulfur during fluid-wall rock interaction. The early, magmatic-hydrothermal Fimiston/Hidden Secret and Oroya gold-telluride lodes differ texturally, geochemically, and mineralogically from the D3 Mt. Charlotte stockwork veins, which formed subsequent to ca. 2650 Ma and better adhere to a late-stage metamorphic devolatilization model.

The Baiyinnuo’er deposit in northern China is located in the south section of the Great Xing’an Range, and it is the largest skarn Zn–Pb deposit in the region. Skarn and Zn–Pb orebodies mainly occur between the different units of the Permian Huanggangliang Formation, or within the contact zone between the intrusive rocks and the marble. Although Baiyinnuo’er has been well investigated previously, the timing of the Zn–Pb mineralization is still controversial, largely due to the lack of appropriate ore or alteration minerals that could be directly used for isotopic dating. In this study, we report the results of Rb–Sr isotopic analysis for sphalerite and pyrite samples from the Baiyinnuo’er orebodies, which yielded two isochron ages of 137.4 ± 3.4 and 140.0 ± 7.8 Ma, respectively, constraining the Zn–Pb mineralization time of the deposit as the Early Cretaceous. The data are also consistent with the age of the granitoids in the mining area, indicating a potential genetic relationship between the Early Cretaceous magmatism and mineralization. Many other intrusion-related hydrothermal deposits (including the two typical skarns, Huanggang and Haobugao) in the southern Great Xing’an Range also share similar mineralization ages (i.e., 140–130 Ma). Together, these data suggest an Early Cretaceous mineralization event in this region, and this large-scale mineralization could be related to the regional tectonic regime transition from compression to extension as a result of the rollback of the subducted Paleo-Pacific plate. The initial 87Sr/86Sr ratios of the sphalerite and pyrite samples are 0.70569 and 0.70616, respectively, implying that the ore-forming material could have a significant contribution from the mantle components. The current study shows that sulfide Rb–Sr dating could be used in deciphering the timing of skarn deposit formation.

Background. Some papers describing the deposits and prospects in the Baimka ore zone (Baimka Trend), the Chukotka Autonomous Region have been recently published. It should be noted that those publications concern with the large Peschanka porphyry copper-molybdenum-gold deposit and Nakhodka ore field. At the same time, some copper prospects were found at the zone flanks and their nature is not clear. There are no data available in the literature that would clarify the mineralogy of hydrothermal alteration and ores at those prospects, including Top and Luchik located at the northern flank. To understand the nature of these prospects, we studied in depth mineralogy of hydrothermal alteration and ores.Aim. This study aims to describe mineralogy of metasomatic rocks and ores from the Top and Luchik prospects in the northern part of the Baimka zone, Western Chukotka.Materials and methods. Several dozen polished thin sections were microscopic studied at the Department of Mineralogy of Moscow State University using an optical microscope. The chemical composition of minerals was determined using electron microprobe at the Laboratory of Analytical Techniques of High Spatial Resolution, Department of Petrology and Volcanology, Moscow State University.Results. It was found that propylitic is the major hydrothermal alteration at the prospects studied here. Metasomatic rocks are cut by mineralized quartz and carbonate-quartz veins. Chalcopyrite and pyrite are the major ore minerals; galena, sphalerite, pyrite enriched in As and Sb, and marcasite are minor; Hg-bearing tetrahedrite-(Zn), native gold with the fineness of ~830, petzite, hessite, and acanthite are rare.Conclusions. The data obtained suggest that mineralization at the Top and Luchik prospect is attributed to the epithermal intermediate sulfidation type. Considering the occurrence of the epithermal mineralization in the upper part of the hydrothermal column and the porphyry mineralization in the Baimka zone, the porphyry mineralization is possible at depth at the Top and Luchik prospects.

This study investigated the geochemistry, mineralogy, fluid inclusion, trace and rare earth element (REE) contents and Pb, O and S isotope results of the barites formed together with Pb-Zn deposits in the region. The Buyukkizilcik barite mineralization is located in the west part of Afsin, Turkey and it can be traced through 14 kilometers in NE-SW direction within the Yoncayolu and Cayderesi Formation. The thickness of these mineralized areas reaches 7-8 m, especially in the middle and eastern part of the ore zone. Mineralization is represented by barite-antimonite-fluorite in the western part, pyrite-chalcopyrite in the middle part and galena-sphalerite in the eastern part of the mineralized zone. Fluid inclusion studies indicate that these mineralizations are formed in the epithermal phase of hydrothermal period, with liquids having 4.5 to 2% NaCl salinity values and temperatures of 105 °C to 121 °C. The barite samples were collected from Buyukkizilcik mineralization area for analysis of major oxides, trace elements, and rare earth elements (REEs) using inductively coupled plasma mass spectrometry (ICP-MS). According to the results of the analysis, it is seen that total trace element contents change from 163 to 20458 ppm and ∑REE contents are between 4.31 and 14.4 ppm. The chondrite- normalized REE patterns of the studied barites exhibit trends decrease from LREE towards HREE and have negative Ce and negative Eu anomalies. The 206Pb/204Pb; 207Pb/204Pb and 208Pb/204Pb isotope values of galena vary between 17.20 and 19.96%o; 14.1 and 16.2%; and 35.4 and 41.9%, respectively. These isotope results show that these mineralizations were originated from upper crust materials. The δ34S values in Buyukkizilcik mineralizations range from 8.2 to 14.4‰. The barite mineralization was formed by hydrothermal activity and that the δ34S values indicate an epithermal phase. The δ18O values of barites are between 17.0 and 18.5‰ and these δ18O values show that the origin of the water displayed in the hydrothermal activity is magmatic and/or magmatic mixed with meteoric water. All results indicate that the barite mineralization was deposited as vein-type by hydrothermal solutions that are transported along fractures and fault zones within the Malatya Metamorphic complexes.

Remote sensing and aeromagnetic data analyses were conducted for the characterization of basement structural elements that influence iron ore deposits and other mineralization over kabba and its surroundings. Spectral analysis suggests depth to magnetic sources range from deep, intermediate, and shallow with depths (i.e., 2.8 km, 1.5 km, and 0.3 km respectively). Three lithological zones were revealed on the Analytic Signal (AS) image which includes Meta-Sedimentary Complex, migmatite-gneiss-quartzite complexes, and undifferentiated schist and metavolcanic rocks. Structures interpreted based on first vertical derivatives (FVD), total horizontal derivatives (THD), and AS of the aeromagnetic images enabled delineation of long, deep, regional, inter-terrain linear structural features that are different f rom shallow, relatively short local intra-terrain structures. Typical potential mineralized zones are regions where the delineated structures on the AS coincide with FVD anomalies vis-a-vis zones exhibiting THD peak anomalies and high magnetic susceptibility. These characterized zones also coincide with the location of known geologically deposits of iron - ore and marble. Mineral deposits tend to be dominated regionally by the dominant structural patterns (NE-SW to ENE-WSW, NW-SE to WNW-ESE, and E-W) delineated from SRTM and aeromagnetic analysis.

Iron ore is the second most abundant metal on earth. The characteristics of this iron ore usually consist of iron ore carrier minerals associated with other minerals. One area that has iron ore prospects is the Tanjung area, Bontocani District, Bone Regency. The purpose of this study was to determine the types of iron ore carrier minerals and their associations, mineralization characteristics and paragenesis of iron ore carrier minerals. The data collection technique is carried out directly in the field by taking random samples in the field according to field conditions. Laboratory analysis uses mineragraphic analysis to determine iron ore carrier minerals and their associated minerals and X-Ray Diffraction analysis to determine iron ore carrier minerals that are not identified by mineragraphic analysis. From the results of the study found iron ore carrier minerals magnetite, goethite and hematite and their associated minerals in the form of sulfide minerals in the form of pyrite, covelite and braunite. The iron ore textures found are replacement and intergrowth textures. Paragenesis of mineral deposits formed successively are magnetite, hematite, pyrite, cuprite, braunite and goethite.

Unravelling the genesis of metamorphosed mineral deposits can be complicated due to difficulties in separating between primary features and features that formed during the metamorphic overprint. Such uncertainty exists for stratabound and dolomite- and skarn-hosted Zn-Pb-Ag sulfide deposits in 1.89 Ga rocks in the Bergslagen lithotectonic unit (BLU) of Sweden, where a metasomatic vs. regional metamorphic origin for skarns has long been discussed. By integrating geological mapping with new lithogeochemical, mineralogical, and stable isotope data (C, O, S), we show that complexly zoned garnet and clinopyroxene skarns in the Sala area of the central BLU predate mineralization. Sphalerite-galena mineralization formed after the deposition of a younger, more Mn-rich ferroan diopside and andradite-grossular garnet, and is associated with phlogopite, tremolite-actinolite, chlorite, serpentine, and calcite. Mineralization in conjunction with a transition from high-T metasomatism to hydrolytic alteration is inferred. An average δ34SV-CDT of 1.6 ± 1.9‰ in sulfides is consistent with a primordial sulfur source. Trends defined by negative shifts in δ18OV-SMOW and δ13CV-PDB in dolomite and calcite are consistent with fluid infiltration at 300–500 °C. The alteration system is sharply truncated by unaltered, c. 1.89 Ga calc-alkaline granite and porphyritic intrusions, which along with F1 folding of the alteration zones and mineralization suggest that mineralization predate regional metamorphism. The Sala deposits are interpreted as Zn skarn deposits formed in conjunction with the emplacement of intrusions into penecontemporaneous marine volcanic and dolomitized limestone strata. The unusually Mg-rich mineralogy in relation to Zn skarns worldwide most likely reflects the dolomitic precursor.

This article investigates the effect of material size on the efficiency of flotation concentration of gold-copperarsenic ores of the Taror deposit (Republic of Tajikistan) and studies the dependence of gold recovery on the duration of the process with the purpose of developing an alternative technological scheme for processing this ore type. According to X-ray phase analysis, Taror ore samples consist of rock-forming minerals by 92%. Ore mineralization is represented by sulphide minerals, mainly arsenopyrite, chalcopyrite and pyrite, in the total amount of 8%. Ore-forming elements include iron, sulphur, arsenic and copper with the mass fraction of 6.02%, 3.26%, 1.52% and 0.82%, respectively. Gold and silver are contained in the ore in the amount of 7.35 g/t and 20.28 g/t, respectively. The oxidation state of the ore calculated by iron comprises 51.3%. According to this indicator, this ore type can be distinguished as mixed, close to the primary type. According to the conducted chemical phase analysis of gold, this ore type belongs to the category of refractory ores. Flotation concentration experiments showed that grinding the original ore to a size of 95%–71 microns increases the recovery of gold in the concentrate by 10%, compared to grinding to a particle size of 80%–71 microns. The effect of the flotation process duration on gold recovery was also studied. To achieve the maximum gold recovery in the flotation concentrate, the duration of the main flotation and control flotation should be taken equal to 14 and 12 minutes, respectively. As a result of the experiments, a relatively simple technological solution was proposed for flotation concentration of the Taror ore, which includes the main, control and cleaning stages of flotation.

The I-type Pan-African Misajé granites, situated in the Western domain of the Central African Fold Belt are among the late-to post tectonic granites that intruded the ante-Pan-African country rocks. In this study, magnetic susceptibility and geochemistry data are integrated to evaluate the productive and non-productive metal potential of these I-type plutonic granites, which comprise Leucocratic granite, Biotite granite, Biotite-hornblende granite, and granodiorites. The magnetic susceptibility of the representative rock samples of the Misajé pluton ranges from 0.001 × 10−3 SI to 33.2 × 10−3 SI. These values indicate the coexistence of both magnetite and ilmenite-series. The magnetite-series (>3 × 10−3 SI; oxidized type) constitute about 32 vol.% while the ilmenite-series ( 1) grains sizes. The Misajé plutonics are high potentially productive in Zn, Th, ilmenite, and magnetite and low productive in Sn, W and Cu though their extension remains limited, probably due to the remobilization of the ancient Paleoproterozoic crust that would have contributed to the dispersing of pre-Pan-African metal deposits.

Precambrian banded iron formations (BIFs) of Singhbhum-Keonjhar-Bonai iron ore belt in eastern India host several high grade iron ore deposits. The deposits have been formed due to supergene enrichment of parent BIFs by gradual removal of SiO2 and Al2O3 under continuous process of leaching. With intensity of leaching differing spatially, the deposits exhibit variation in Fegrade both laterally and vertically. The extent of such variation in space is a function of the scale at which observations are made. Modelling of spatial variabilities at observation scale provides an appropriate means to estimate spatially distributed block values. The present study focusses on spatial variability analysis, ordinary kriging (OK) and sequential Gaussian simulation (SGS) for Fegrade modelling using drill-hole exploration data of a high grade iron ore deposit located in the Singhbhum-Keonjhar-Bonai iron ore belt. Classical statistical modelling revealed a three-parameter lognormal fit to the negatively skewed Fe distribution, and a two-parameter lognormal fit to the positively skewed SiO2 and Al2O3 distributions. Spatial variability modelling revealed a spherical model fit in respect of Fe, SiO2 and Al2O3. A moderately high ratio of nugget-to-sill variance reflect intrinsic characteristic of banded nature of Fe mineralization as evident in BIFs with varying proportions of iron, alumina and silica. Blocks of 15m × 15m × 10m size equalling the dimension of a mining unit configured within a 3D volume bounded vertically between 875 mRL and 705 mRL and laterally between 310W to 540E and 260S to 1600N have been evaluated employing OK. Stacking of altogether seventeen horizontal slices vertically down from 870 mRL to 710 mRL led to an estimate of iron ore inventory as 124.48 mt with overall mean kriged estimate as 63.93% and mean kriging variance as 2.83 (%)2. Statistical regression analysis of OK estimates and original sample values provided a regression slope of 1.03, thereby qualifying the conditional unbiasedness of the OK estimates. SGS study provided multiple equi-probable realisations with histogram and spatial variability closely approximating to that of the original sample values.

The Masjed Daghi porphyry-epithermal Cu-Au-Mo deposit in the northern Arabian-Eurasian collision zone of the Alborz Magmatic Assemblage, NW Iran, is hosted by an early Miocene quartz monzodiorite to diorite intrusion that intruded Eocene volcanic rocks. Potassic, phyllic, argillic, and propylitic alterations associated with four stages of porphyry mineralization (I to IV) are distinguished. Late high-sulfidation epithermal veins of mainly quartz or quartz-barite are enclosed in concentric zones of advanced argillic, argillic, silicic, and propylitic alterations. Poly-phase brine inclusions from the stage ΙΙ porphyry mineralization have homogenization temperatures (Th) between 305 and 600 oC, with salinity from 30.2 to 73.9 wt% NaCl equivalent. Brines inclusions of stages ΙΙΙ and ΙV have Th from 192 to 466 oC and salinity from 20.6 to 59.2 wt% NaCl equivalent. These brine inclusions were trapped with vapor-rich inclusions, which have Th from 122 to 318 oC and low-moderate salinity of 0.3 to 22.3 wt% NaCl equivalent. Fluid inclusions from quartz and sphalerite in epithermal veins yielded Th ranges of 123–298 °C and 121–218 °C, and salinity ranges of 1.9–12.8 and 1.9–11.2 wt% NaCl equivalent, respectively. The δ34S values of sulfide minerals from stages ΙΙ and ΙΙΙ porphyry mineralization vary from + 0.9 to + 2.3‰, whereas the δ34S values of sulfides from the late epithermal veins range from + 1.2 to -1.1‰. These characteristics are consistent with a similar magmatic source for both the fluids of porphyry mineralization and subsequent high-sulfidation epithermal veins. The Masjed Daghi deposit that represents a telescoped porphyry-epithermal system of copper–gold mineralization in the center and peripherals of the early Miocene intrusive stocks shows both similarities and differences to other Tethyan deposits in the Alpine-Himalayan orogenic belt.

The world-class McArthur River Zn-Pb-Ag deposit is the type example of stratiform sediment-hosted deposits found in the Proterozoic basins of northern Australia. However, the McArthur River deposit is enigmatic in that, aside from a few sub-economic deposits within the same camp, other deposits of this type have not been discovered regionally. Understanding the key components of McArthur River-type mineral systems and the regional distribution of these components is crucial to further discovery. The recent discovery of the similar but pyrite-dominated system at Rosie ~ 90 km north of the McArthur River Mine sheds new light on the formation of this deposit class and provides a counterpoint to compare and contrast with the high base metal endowment at McArthur River. Stratiform pyrite mineralization at Rosie is finely laminated and is affected by erosional sedimentary processes superficially indicating it formed during sedimentation to early diagenesis and at or near the sediment–water interface. The conventional ore horizon in the McArthur River camp is the HYC Pyritic Shale Member in the lower Barney Creek Formation (~ 1640 Ma) within sub-basin architecture. Rosie is contained within a similar sub-basin architecture, but it occurs in the upper Barney Creek Formation. The absence of mineralization in the lower Barney Creek Formation at Rosie is attributed in part to prohibitive tectono-sedimentary conditions during early sub-basin development. The HYC Pyritic Shale Member equivalent is relatively thin beneath the Rosie mineralization and is only weakly enriched in hydrothermal elements. Its deposition was abruptly superseded by infill of the sub-basin by a thick barren sequence of fine turbidites. The fine turbidites were a rapid phase of accommodation space fill that diluted brines entering the sediment pile and effectively precluded hydrothermal sulfide mineralization as well as low temperature alkali metasomatism. Permissible tectono-sedimentary conditions did not return until late in sub-basin development, and by this time, sub-basin geometry had broadened and shallowed, and the hydrothermal fluid had evolved. Rosie mineralization is subsequently poorly focused and base metal deficient. The observation that sedimentation rate may play a role in mineralization is a significant addition to the field of basin-hosted mineral systems.

Palladium mineralization was registered in the Kola superdeep borehole (SG-3) for the first time in samples from deep horizons (in the fault zone at ~10 km). A proper palladium mineral (merenskyite) with the formula Pd1.00(Te1.21Bi0.79)2.00 was detected using the analytical electron microscopy and EBSD methods. The unusually high content of bismuth in the discovered merenskyite crystal most likely indicates the lower temperatures of its formation from a bismuth-rich fluid. This is supported by numerous finds of associated bismuth minerals (native and intermetallic minerals, sulfides, tellurides, and sulfotellurides) as well. A close geochemical association of noble and rare elements was revealed in the composition of the rich and diverse ore mineralization in the samples studied. It can be argued that a new type of mineralization was discovered for the SG-3 rocks: noble metal (Au–Ag–Pd) rare-element (Bi–Te).

The Laowan super-large (208 t Au) gold deposit is located in the Tongbai orogenic belt, along with a newly-discovered molybdenite deposit at its depth in the northern periphery. The gold deposit is a fault-controlled lode gold deposit featuring sulfide quartz vein-type and altered rock-type mineralization hosted within the metamorphic rocks, whereas the molybdenum deposit is a typical porphyry-type deposit. These two deposits have their respective paragenetic sequences and mineralization types without spatial overlapping in the ore field. Here, we present U–Pb dating of zircon, hydrothermal rutile, and REE phosphates, and Re–Os dating of molybdenite to constrain the relationship between the Au and Mo mineralization, and their relation to Mesozoic granitic magmatism. Textural features indicate that rutiles and associated phosphate minerals are of hydrothermal origin, generated by re-precipitation and dissolution of titanite crystals hosted in the metamorphic host rocks due to hydrothermal alteration during Au and Mo mineralization. LA-ICP-MS U–Pb dating of rutile from the auriferous altered rocks yields a 206Pb/238U age of 120.0 ± 6.7 Ma (MSWD = 1.4), consistent with the ages of the associated monazite (125.0 ± 2.4 Ma) and xenotime (126.3 ± 2.0 Ma), representing the timing of the gold mineralization, coeval with Laowan monzogranite (zircon U–Pb: 128.8 ± 0.7 Ma). Rutile from the molybdenum deposit show an older 206Pb/238U age of 141.0 ± 11 Ma (MSWD = 1.1), consistent with the molybdenite Re–Os age (141.5 ± 1.7 Ma; MSWD = 0.27) and the zircon U-Pb age (141.6 ± 0.8 Ma; MSWD = 1.5) of the Songpa porphyry. Hence, the Au and Mo mineralization in the Laowan district represent two episodic mineralization events related to the late Mesozoic granitic magmatism. Our study also suggested that multiple isotopic dating is helpful to precisely constraint the ages for complex hydrothermal deposits.

The Sopcha massif, which is part of the Paleoproterozoic layered Monchegorsk Pluton (Monchepluton), contains an ore horizon with an average thickness of ca. 4 m within the homogeneous orthopyroxenite sequence. This horizon has a layered internal structure with variations in composition from dunite to orthopyroxenite and sulfide mineralization enriched in platinum group elements (PGE). All the rocks of the ore horizon include accessory chrome-spinels, which demonstrate a high variability of the composition and are divided into two groups based on their optical properties and chemical composition. Group I chrome-spinels belong to Al-chromites. They occur as homogeneous grains in fine-to-medium-grained orthopyroxenite at the top of the horizon and form cores of zoned chrome-spinels in the medium-to-coarse-grained orthopyroxenite and harzburgite. Group II chrome-spinels belong to Fe-chromites. They form homogeneous grains in dunite and harzburgite and rims of zoned grains in harzburgite. Chemical compositions of Group I chrome-spinels are characterized by high contents of Al2O3 and Cr2O3, an increased MgO but low contents of FeOtot and values of Cr#= Cr/(Cr + Al) and Fe3+# = Fe3+/Fetot. Group II chrome-spinels have low Al2O3 and MgO contents, and sharply increased values of Cr# and Fe3+#. This variability in the composition of chrome-spinels is caused by decreasing melt temperature in the process of its cooling during two stages of magmatic crystallization. At the first stage, cumulus crystallization of Group I chrome-spinels and subsolidus diffusion between spinel and olivine (“mineral-mineral” reaction) occurred at a temperature of about 1170 °C. At the second stage, reactions between Group I chrome-spinels and intercumulus melt (“mineral-melt” reactions) resulted in the formation of a rims of zoned chrome-spinels and homogeneous Group II chrome-spinels at a temperature of 1070–970 °C.

The gold deposits in the Jiaodong Peninsula constitute the largest gold mineralized province in China. The mineralization shows common characteristics in their tectonic setting, ore-forming fluid and metallogenic system. Sulfidation and fluid immiscibility are two important mechanisms controlling gold precipitation, both of which consume sulfur in the ore-forming fluids. The escape of H2S from the main ore-forming fluids and the decrease of total sulfur concentration not only lead to the efficient precipitation of gold, but also result in the crystallization of reducing minerals such as pyrrhotite and oxidizing minerals such as magnetite. Quartz solubility shows strong dependence on temperature, pressure, and CO2 content. The dependence of quartz solubility on pressure is weak at low temperatures, and progressively stronger at higher temperatures. Similarly, the temperature dependence of quartz solubility is relatively low at low pressures, but becomes gradually stronger at high pressures. The results of solubility modeling can constrain the dissolution and reprecipitation behavior of quartz in the ore-forming veins and the formation mechanism of different types of quartz veins. The multi-stage mineralization fluid activity resulted in the complex dissolution structure of quartz in the Jiaodong gold veins. Pyrite in the main metallogenic period in the Jiaodong gold deposits shows complex microstructure characteristics at single crystal scale. The trace elements (mainly the coupling of As- and Au-rich belt) and sulfur isotope composition also display a certain regularity. The As-rich fluids might have formed by the initial pulse of ore-forming fluids through As-rich metasedimentary strata, while the As-Au oscillation zone at the margin of pyrite grains is related to the pressure fluctuation caused by fault activity and the local phase separation of fluids. There is a temporal and spatial evolution of gold fineness in the Jiaodong gold deposits. Water/rock reaction (sulfidation) was the main ore-forming mechanism of early gold mineralization, forming relatively high fineness gold, while significant pressure drop in the shallow part accompanied by fluid phase separation promoted the late gold mineralization, forming low fineness gold. Under cratonic destruction setting, dehydration of the amphibolite and granulite facies metamorphic lower-crust resulted in the formation of Au-CO2-rich ore-forming fluids, which rose along the deep fault and secondary structure, and formed the largescale fault-controlled gold deposits in Jiaodong.

The late Palaeozoic Yong’an–Meizhou depression belt is an important iron (Fe) and polymetallic metallogenic belt in southern China. It has undergone a transformation from Tethys to the circum-Pacific tectonic domain. The Luoyang deposit is one of the typical Fe skarn deposits in the Yong’an–Meizhou depression belt of eastern China. Garnet is a characteristic mineral in the deposit. Two generations of garnets are detected in the deposit based on their textural characteristics and trace-element contents, and are represented by Fe-enriched andradite. The first generation of garnets (Grt1) have two types of garnets (Grt1-A and Grt1-B). Type A garnets of the first generation (Grt1-A) (Adr80-88) replaced by massive diopside-magnetite assemblage exhibit distinct oscillatory zonings and display patterns of enriched light rare earth elements (LREE) to weak heavy rare earth elements (HREE), with weak negative to positive Eu anomalies, and highest U, ΣREE and Sn contents. Type B garnets of the first generation (Grt1-B) are irregular zones (Adr94-96) coexisting with magnetite, in which Grt1-A is generally dissolved, and have obviously LREE-enriched and HREE-depleted patterns, with weak negative to positive Eu anomalies, and moderate U, ΣREE and Zn contents. Garnets of the second generation (Grt2) (Adr96-99) that replaced massive magnetite together with sphalerite show unzoned patterns, with a flat REE pattern and pronounced negative Eu anomalies as well as contents of lowest U and ΣREE, and highest W. The substitution of REEs in garnets occurs as [X2+]VIII –1[REE3+]VIII +1[Si4+]IV –1[Z3+]IV +1in an Al-enriched environment. Luoyang hydrothermal fluids shifted from reducing conditions with relatively high-U and -ΣREE characteristics to oxidizing conditions with relatively low-U and -ΣREE characteristics. The reduced siderophile elements and increased fO2 in fluid during Grt1-B formation caused magnetite mineralization and reduced Zn contents during Grt2 formation, causing the deposition of sphalerite. All garnets formed from magmatic fluid and were controlled by infiltrative metasomatism in an opened system.

The Kapalagulu intrusion in eastern Tanzania hosts a major, 420-m-thick, stratiform/stratabound platinum group element (PGE)-bearing sulfide zone—the Lubalisi reef—within a prominent, chromititiferous, harzburgite unit close to its stratigraphic base. Several features of the vertical base and precious metal distributions (in a composite stratigraphic section based upon two deep exploration drill holes) display similarities to those of offset-type PGE reefs that formed under the overall control of Rayleigh fractionation: (1) composite layering (at several scales) defined by systematic vertical variations of sulfide and precious metal contents and intermetallic ratios, indicating repeated cycles of PGE enrichment and depletion in the order Pd-Pt-Au-Cu, and (2) in the lower part of the reef, stratigraphic offsets of the precious metal peaks below peak sulfide (Cu) content. The form and geochemistry of the reef are consistent with overturns of basal liquid layers within a liquid layering system (i.e., stable density-driven stratification of a magma chamber), plus at least two minor inputs of parental magma during which the resident magma was recharged with sulfur and metals, and the effective depletion of precious metals in the magma midway through reef development. The Lubalisi reef differs from classic offset-type PGE reefs, however, principally because individual Pd, Pt, and Au enrichment peaks are coincident, not offset. The reef is set apart from other offset-type PGE reefs in three additional ways: (1) its association with olivine cumulates that crystallized soon after initial magma emplacement and well below the first appearance of cumulus pyroxene or plagioclase (implying attainment of sulfide saturation and precious metal enrichment without prolonged concentration of sulfur and chalcophile metals by normal magma cooling and differentiation), (2) the probable role of chromite crystallization in not only triggering sulfide segregation during reef formation but also facilitating precious metal enrichment in the early stages of reef development, and (3) its great width. The early stage of fractionation may also help explain the coincident precious metal peaks through its effect on apparent precious metal partition coefficients.

The Hehuashan sediment-hosted Pb–Zn deposit is a large-scale (Pb + Zn＞1 Mt) deposit hosted in the Tongling mining district of the Middle-Lower Yangtze River belt (MLYB). The Pb–Zn ore bodies are composed of two main mineralization types, namely breccia type and massive type. The breccia type ore bodies are hosted by the Triassic limestone and dolostone, while the massive ore bodies are hosted by marble dolostone which are close to the diorite intrusions. The previous research showed that the Hehuashan Pb–Zn deposit is a Mississippi Valley-type (MVT) deposit formed in Middle Triassic and overprinted by late mineralization of magmatic-hydrothermal fluids in Yanshanian period. In this research, we aimed to declare the age of the late mineralization and it's relationship with diorite intrusions. The mineralization age (132.8 ± 3.1 Ma) of the massive ore rocks (late mineralization) is similar to the zircon U–Pb age of the diorite (133–130 Ma), showing that this type mineralization is contemporaneous to the Yanshanian intrusive events. Furthermore, similar initial 87Sr/86Sr values between sphalerite and diorite indicating a magmatic fluid was involved during the mineralization process and the emplacement of diorite also might have provided ore-forming materials. The heavy sulfur compositions (δ34S = +8.6‰ to +12.8‰) of the sphalerite in massive ore rocks indicate that the sedimentary sulfate may have provided reduced sulfur for sulfides precipitation by sulfate thermochemical reduction process. Sr–Nd isotopic compositions of the diorite in the Hehuashan deposit area showed that the massive Pb–Zn mineralization was related to the intrusion of diorite in an extensional tectonic setting. In summary, the Hehuashan Pb–Zn deposit composes a late Yanshanian Pb–Zn mineralization event and represents a younger Pb–Zn mineralization in the Tongling district and MLYB. The Triassic carbonates have the potential for Pb–Zn deposit exploration in the Tongling district and Middle–Lower Yangtze River belt.

Numerous silicate, Fe-oxide, and Cu–Au–Ag microspherules are found in Fe ores and pyroclastic rocks of the Kostenga deposit, Lesser Khingan (Far East of Russia). The silicate spherules contain immiscible Fe and Si glasses, vapor voids, and mineral inclusions. The Fe-oxide spherules host magnetite with a small amount of ilmenite and Fe-rich silicate glass. The Cu–Au–Ag spherules contain inclusions with dominant CuO in their composition. These microspherules are considered to form due to rapid uplift and degassing of liquation-differentiated ore-silicate melts. The possible volcanic formation of ores and precious metal mineralization is discussed for these types of the deposits.

A structural interpretation of the first Re–Os dating of pyrite and arsenopyrite from the Malinovsky gold deposit is given. Comparison of the obtained data and the known ages of ore-bearing granitoids from the ore field made it possible to determine the age of mineralization as 100–90 Ma. This age corresponds to the time of completion of the Albian–Cenomanian geodynamic setting of the transform margin of the Asian Continent with significant left-shear dislocations, as is evident from the structural patterns of localization of ore bodies and magmatic rocks. The time interval and geodynamic conditions for the formation of the Malinovka deposit are similar to those of many gold and gold-bearing deposits within the Sikhote-Alin orogenic belt and the south of the Korean Peninsula.

The Gol’tsovoe Ag–Pb–Zn-deposit (1600 t silver in ores with an average grade of 1025 g/t Ag) is located on the southeastern flank of the Dukat mining district, at the junction of the Balygychan–Sugoi rift trough and the Okhotsk–Chukotka Volcanic Belt (OCVB). The Dukat district is the largest silver producer in Russia. The Gol’tsovoe deposit is located 2 km north of the Pestraya granitoid intrusion, in the structurally complex zone of a fault contact of the Upper Triassic terrigenous sediments and Late Cretaceous volcanic rocks. The contact consists of a series of fault planes within a 0.5–1 km wide belt, along which the western block, composed of felsic volcanics, has been downthrown more than 1 km. The host Upper Cretaceous rhyolitic and rhyodacitic ignimbrites are intruded by subvolcanic nevadite bodies. A characteristic feature of the deposit is the occurrence of en-echelon galena veins and veinlets with high Ag grades at the upper levels of orebodies. Massive, coarsely banded, and spotted ore structures are predominant. Ore geochemistry agrees well with the mineral composition. The ores are enriched in a wide spectrum of elements: Ag, Sb, Pb, Cd, As, Zn, Bi, In, W, Sn, Mn, Cu, Li, Tl, and Cs. They are characterized by a low total REE abundance (33.34–50.69) and a negative lanthanide distribution type. Commercially significant potential by-products are Cd, In, and Bi. Galena is the main Ag mineral concentrator: the high Ag concentrations in this mineral are due to the occurrence of small inclusions of a large group of independent Ag-bearing minerals, argentotetrahedrite and pyrargyrite especially, and a small amount of myargirite, polybasite, etc. Argentite and native Ag occur in limited amounts. Tin minerals are represented by stannite, canfieldite, and less frequent cassiterite. Oxidation zone has been tracked over the entire mineralization depth and displays a pronounced linear trend. Oxidized ores are dominated by Zn, Pb, Fe, Ca, and Ba sulfates; less abundant Fe, Mn, and Zn oxides; and subordinate carbonates and clays; total sulfides and native metals (Cu, Ag) do not exceed 2%. Ore oxidation degree is 40.3%. The sulfide–quartz–chlorite veins of the Gol’tsovoe deposit formed at moderate temperatures (276–138°С) from low-concentration chloride hydrothermal fluids (4.2–0.2 wt % NaCl eq.), saturated with Na and К cations and Mg in subordinate amount. The obtained data allow the Gol’tsovoe deposit to be classified as an epithermal intermediate sulfidation deposit. A two-stage ore emplacement model is proposed. During the first stage Ag–Pb–Zn ore was emplaced as a result of the functioning of a near-surface hydrothermal system of volcanic origin. During the second stage, imprinted Sn mineralization was emplaced in the Ag–Pb–Zn ore veins as a result of tin-bearing magmatogenic fluid inflow at the lower levels of the deposit.

Tirtomoyo in Wonogiri district is known as an ore mineralization region, in which one of the prospects occurred is Hargosari. No previous studies on the ore characteristucs have been done. A set of study on Hargosari prospect is aimed to characterize gold mineralization covering some aspects such as mineralogy, textures, ore chemistry and ore forming condition. To achieve the objectives, some research methods were performed suh as mapping, sampling and laboratory analyses for selected samples on term of petrography, ore microscopy and ore chemistry. Oligo-Miocene andesitic lava from Panggang Formation is identified as host rock. Opening system of veins is of jogs type to form en-´echelon tension gash veins. Quartz veins are enveloped by argillic and propylitic alteration zones, in association with pyrite, chalcopyrite, sphalerite, galena, gold, silver, chrysocolla, covellite and hematite. The approximately 5 cm thick quartz veins exhibit massive, swarm, low angle veins and stockwork structures, which is characterized by normal banded, crustiform, comb and saccaroidal textures. The quartz veins contain high base metals of up to 5.45% Cu, 9.9% Pb and 12.85% Zn, with significant grade of gold and silver of up to 3.85 g/t Au dan 395 g/t Ag. From mineral assemblages, the veins might be formed at temperatures of about 250-300°C. On the basis of those mentioned characteristics, gold mineralization in Hargosari prospect is categorized into an intermediate sulfidation epithermal. Keywords: characteristics, gold, epithermal, Hargosari, Wonogiri.

In this work, mineralogical and geochemical data are presented for sulfide-rich phoscorites and carbonatites in the Kovdor massif. The PGE and Ag-bearing mineralization of bornite–chalcopyrite and Ag‑bearing mineralization of pyrrhotite–chalcopyrite associations were investigated. In carbonatite stage formation of massif, the noble metal minerals occurred during evolution of alkaline–ultrabasic melt and after separation of primary sulfide melt enriched in PGE, Au and Ag. According to the observed relationships, the minerals of PGE, Au, and Ag in bornite–chalcopyrite association are crystallized sequentially from magmatic to hydrothermal stages. Crystallization of Os, Ir, Pt and Pd minerals (erlichmanite, rustenburgite, isoferroplatinum, mertieite–II, etc.) occurred at temperature close to 480°С, while further decrease in the temperature and an increase in the Cu and Fe activity in the melt leads to the crystallization of Sb, Pb, As, Bi and Te-bearing minerals (sperrylite, tatyanaite, moncheite, stumpflite, etc.). Formation of Au and Ag-bearing minerals (electrum, silver, stromeyerite, lenaite, etc.) occurred at temperatures below 300 °C with relatively low sulfur activity. In carbonatites and phoscorites of the middle and late magmatic stages enriched with magnetite, pyrrhotite–chalcopyrite association with silver-bearing minerals was formed at temperatures below 300°C. Ag-bearing minerals were produced during hydrothermal recrystallization of Cu–Fe–Ni sulfides at temperature close to 150°C.

Exploration and mining success of a bauxite deposit rely greatly on an adequate modelling of spatial characteristics of constituent geo-variables through an understanding of deposit geology, because it is the geology that governs the process of mineralisation and geostatistics provide its meaningful role in spatial characterization of constituent geo-variables. Geostatistical modelling and subsequent study of vertical variation provide an objective means to spatial interpolation of sample values within the mineralization limits of bauxite deposit at specified cutoffs of alumina and silica. On the basis of an adequate understanding of the genesis of bauxite mineralization, an integrated study has been carried out to analyse geological, statistical and geostatistical characteristics of an east coast bauxite deposit of Odisha, India. Due to prolonged residual concentration and lateralization of Precambrian khonadalites and charnokites, the bauxite deposits formed is geologically ferruginous type (high in iron) and spatially heterogeneous. Modelling results from statistical and geostatistical analyses have been interrelated to the process of formation together with an understanding of the vertical variations in the ferruginous bauxite deposit. Spatial correlation of the constituent geo-variables reveal a range of influence varying between 170 to 310 m and ratio of nugget-to-sill variance varying between 0.58 and 0.78. Sequential Gaussian simulation (SGS) has been carried out in respect of Al2O3 and SiO2 to generate multiple realisations. The SGS study revealed that the mean, variance, and semi-variogram of SGS values are consistent with the original sample values, thereby providing an improvement over the block kriging procedure. Vertical effect analyses of kriged estimates of Al2O3 and SiO2 with depth in the bauxite deposit is phenomenally related with the depositional process of residual concentration. The modelling study emphasises the fact that geology is a key factor in mineral deposit evaluation and when combined with statistical and geostatistical procedures provides a cogent deposit appraisal.

The Baiyangping Cu–Ag polymetallic ore district is located in the northern part of the Lanping-Simao foreland fold belt, between the Jinshajiang-Ailaoshan and Lancangjiang faults, and the deposit can be divided into eastern and western ore zones. Based upon microscope observation of ore minerals and analysis of zinc, copper, and strontium isotope composition, we conclude that: (1) the zinc isotopic compositions of sphalerite from the eastern and western ore belt of the Baiyangping polymetallic ore deposits are enriched in both the heavy (− 0.09‰ to + 0.15‰) and light (− 0.19‰ to − 0.01‰) zinc isotopes. Rayleigh fractionation is likely the additional factor controlling the observed temporal and spatial variations in zinc isotopes in the two studied ore zones. The zinc isotopic composition in the Baiyangping polymetallic Pb–Zn deposits may have the same fractionation as that of magmatic-hydrothermal, VHMS, SEDEX, and MVT deposits, as demonstrated by geological and other geochemical evidence; (2) the range of δ65Cu in massive tetrahedrite is from − 0.06‰ to + 0.12 ‰ that relates to the early stages of ore-formation, which are higher than that of venial chalcopyrite (from − 0.72‰ to − 0.07‰) formed at a late ore-forming stage in the western ore belt. Different ore-forming stages and alteration or leaching processes are likely the main factors controlling the observed variations in copper isotopes in the western ore zone; (3) the 87Sr/86Sr value of hydrothermal calcite in eastern (0.7080–0.7093) and western (0.7085–0.7113) ore belt suggested that mineralization of early calcite, with 87Sr/86Sr values much higher than in ancient Late Triassic seawater, may be related to recrystallization from a radiogenic Sr-rich or silicifying fluid, either from the strata that the ore-forming fluid flows through or from other fluids.

А new Vovchansk Uranium Ore district is allocated within the Orikhiv-Pavlohrad structural-metallogenic zone (SMZ) of the Azov metallogenic region. It is represented by Dibrova REE-U-Th deposit and a number of less studied ore occurrences. This deposit, according to ore mineralogy and age, geological and structural features, can be related to potassium-uranium metasomatite type. Dibrova deposit is considered to be possible analogue of mineralization of the Central Ukrainian Uranium Ore district. Among the main diagnostic characteristics of Dibrova deposit are: 1) location within the Mesoarchean trough-like structure superimposed on the Paleoarchean basement. 2) Spacial and genetic association with Paleoproterozoic two-feldspar granitoids of Dibrova type, which are considered to be related to Saltychia intrusive complex. 3) Regional and local faults, favorable for emplacement of numerous bodies of aplite-pegmatitic granitoids and associated intensive metasomatic alterations of rocks. The flexural fold was formed at the intersection of multidirectional faults, which is also favorable for ore mineralization. 4) Mineralization is confined to metasomatically altered aplite-pegmatites, less often to microcline quartzites of Dibrova suite. 5) K2O/Na2O ratio of ore-bearing granitoids reaches 3.5 and thorium-uranium ratio varies from 1.0 to 4.0. 6) Ores are composed by quartz (70–90 %) as predominant mineral and microcline. Minor minerals (up to 10–15 %) are represented by sillimanite, muscovite, biotite. 7) Accessory minerals include monazite, zircon, rutile, nasturan, brannerite, uraninite, molybdenite. 8) Among trace elements are niobium, lead, molybdenum, bismuth, copper, zinc and tin. Economic REE-U-Th mineralization was da­ted at 1.9–2.2 billion years. It is formed through circulation of hydrothermal-metasomatic fluids associated with the emplacement of Paleoproterozoic aplite-pegmatitic granites of the Dibrova type. Study of monazite and uraninite inclusions by the CHIME techniques confirms the Paleoproterozoic age of mineralization, 2085–2115 Ma. At the same time, the influence of Mesoarchean Yanvarske granitoids for the formation of REE mineralization during early pre-ore stage is not excluded.

The article describes Reza gold deposit of Ugur exploration area located in Geda- bek Ore District of the Lesser Caucasus in NW of Azerbaijan. It is established that main mineralization in the Reza gold deposit consists of hematite-barite-quartz-kaoline veins- veinlets and breccia, pyrite stock-stockverk and quartz-sulfide veins. On the main orebody surface center secondary quartzites with vein-veinlets barite-hematite mineralization have occured over which remain accumulations of hydrous ferric oxides cementing breccias of quartz and secondary quartzites. “Reddish mass” is also observed in erosion parts, being an oxidation product of stock and stockverk limonite-hematite ores. Representing typical gossans, these accumulations by the data of trenches for thickness about 5-10 m contain gold 0.3-3.5 ppm and silver 1.0-45.0 ppm. There are three zones of gold mineralization within the Reza gold deposit: oxide mineralization; transition zone mineralization; sulfide mineralization. The oxide gold mineraliza- tion consists of clay-gravel weathering crust of kaolinite type. The gold-bearing mineralization has been oxidized to a depth of ap- proximately 50-100 meters. Typically, the gold mineralization is coarser and a minor increase in gold grade occurs within the oxides compared to the original rocks. The nugget effect increase in the gold grade of the oxides does not exceed approximately 10%. Deposit alteration signature has characteristics which suggest the current outcrop level may be near the top of a mineralized, gold-bearing high sulfidation epithermal (HSE) system. The gold mineralization at the deposit is interpreted as forming in shallow high sulfidation epith- ermal systems. The mineralization has been noted in well-confined hydrothermal breccia and associated with pyrite stock-stockwork. The majority of the deposit material and current estimates are formed within the barite-hematite-quartz-kaoline mineralization in the secondary quartzite rocks. The main brecciation and stockwork are hosted within secondary quartzite, sometime massive silicified andesite porphyritic rocks.

Pyrite geochemistry has proven useful for tracking changes in the composition and physico-chemical conditions of hydrothermal fluids in ore-forming environments. Here, we investigated the microtextural features and chemical composition of pyrite, a main Au-bearing phase in the Akeshi and Kasuga deposits (Southern Kyushu, Japan), to better constrain the ore-forming processes in these high-sulfidation epithermal Au deposits. Despite the widespread distribution of Au-bearing pyrite in both deposits, no visible Au minerals coexist with pyrite. However, in situ laser ablation inductively coupled plasma mass spectrometry results show that Au concentrations in pyrite vary from below the detection limit to 41 ppm and are positively correlated with Cu (r = 0.4; up to 7400 ppm) and Bi concentrations (r = 0.44; up to 640 ppm). In both deposits, high Cu and Au concentrations occur in small (< 25 μm) anhedral grains of pyrite, which are interpreted to have rapidly crystallized from the ore-forming hydrothermal fluid. In addition, dissolution–reprecipitation textures and thin, concentric, Cu-rich overgrowths were identified in a number of larger (> 25 μm) pyrite grains and aggregates. These abrupt changes in the trace element compositions of pyrite grains likely record episodic metal-rich fluid inputs. We also propose that gold adsorption onto growing pyrite surfaces played a key role in the mineralization of these deposits.

Proterozoic limestone in a north British terrane contains a newly recognised occurrence of Nb-REE minerals. The mineralized Loch Shin Limestone is in the Lewisian Complex of the Northern Highlands ...

The paper presents data on noble-metal mineralization in carbon-bearing rocks of the Sarma Group in the southern flank of the Baikal inlier of the Siberian craton basement. The phase composition of the accessory ore minerals (pyrite, arsenopyrite, microinclusions of native Ni, Sn, Zn, Cu, Fe–Ni and Ni–Fe–Ti composite compounds, Cu and Pb sulfides, rutile, monazite, zircon, and barite) were determined by X-ray microanalysis. Gold, silver, and all elements of the platinum group were determined by scintillation arc atomic emission spectrometry in rock samples from the Ilikta and Hulurtui formations. These elements occur as particles of native noble metals, their intermetallic compounds, sulfides, arsenides, selenides, and sulfosalts. Noble-metal mineralization in the Hulurtui and Ilikta formations of the Sarma Group is proved to be genetically related to tectono-metasomatic processes that affected the primary metasedimentary rocks.

The article presents the results of a comparative analysis of fluorite from various mineralization types of the Saf’yanovka massive sulfide deposit in the Central Urals. The predominant green fluorite is intergrown with barite, quartz, and carbonates in hydrothermal colloform and massive pyrite, veinlet–disseminated chalcopyrite–pyrite–sphalerite and pyrite–chalcopyrite ores, as well as in hydrothermally altered rhyolite. In colloform pyrite ore, fluorite together with galena, sphalerite, chalcopyrite, fahlore, and barite fills interstices between crystals. In altered rhyolite, yellow-green fluorite occurs as veins of 1 cm thick, 2–3 cm pockets, and intergrowths with quartz, carbonate, and barite. The rare-earth element (REE) and yttrium concentrations have been determined by ICP-MS. The highest Y content (160 ppm) is measured in fluorite from metasomatic rock; the intermediate Y content (40–130 ppm) is determined in fluorite from pyrite ore, and the lowest one (4–9 ppm) is typical of fluorite from chalcopyrite–pyrite–sphalerite and chalcopyrite ore. The total REE content in fluorite is 70–150 ppm (chalcopyrite–pyrite–sphalerite and chalcopyrite ore), 100–280 ppm in pyrite ore, and reaches 180 ppm in altered rhyolites. The highest REE concentration is caused by the presence of xenotime, goyazite, monazite, barite or apatite inclusions in fluorite. The Tb/La and Tb/Ca ratios suggest that fluorite resulted from hydrothermal processes. The REE distribution patterns with an evident Eu anomaly (Eu/Eu* > 1) show enrichment in LREE. Positive Eu anomalies reflect the high-temperature conditions (≥250°C) during fluorite crystallization. The pressure-corrected (~100–150 bar) temperature of fluorite formation is 190–260°С.

The Tengshan'ao Sn deposit, located at the Dayishan ore field, Nanling Range, is one of the recently explored deposits in this region. In this study, LA-MC-ICP-MS cassiterite U–Pb and muscovite 40Ar-39Ar isotopic dating analyses for altered granite-type Sn ores yielded ages of 156.7 ± 4.3 Ma and 151.1 ± 1.5 Ma, respectively. These ages are consistent to the LA-MC-ICP-MS zircon U–Pb age of the fine-grained two-mica monzogranite (158.2 ± 1.6 Ma), indicating a coeval magmatism and mineralization for the Late Jurassic Tengshan'ao Sn deposit. It is further demonstrated that the formation of this deposit is related to the Early Yanshanian (160-150 Ma) large-scale diagenesis and mineralization in Nanling Range. It is suggested that the late-stage fine-grained two-mica (muscovite) granite has an indicative significance for searching the altered granite type Sn polymetallic mineralization.

In the northwestern margin of the Youjiang basin (NWYB) in SW China, many Carlin-like gold deposits are highly antimony (Sb)-rich, and many vein-type Sb deposits contain much Au. These deposits have similar ages, host rocks, ore-forming temperatures, ore-related alterations and ore mineral assemblages, but the Au and Sb metallogenic relations and their ore-forming process remain enigmatic. Here we investigate the large Qinglong Sb deposit in the NWYB, which has extensive sub-economic Au mineralization, and present a new metallogenic model based on in-situ trace elements (EPMA and LA-ICP-MS) and sulfur isotopes (NanoSIMS and fs-LA-MC-ICP-MS) of the ore sulfides. At Qinglong, economic Sb ores contain coarse-grained stibnite, jasperoid quartz and fluorite, whilst the sub-economic Au–Sb ores comprise dominantly veined quartz, arsenian pyrite and fine-grained stibnite. Three generations of ore-related pyrite (Py1, Py2 and Py3) and two generations of stibnite (Stb1 and Stb2) are identified based on their texture, chemistry, and sulfur isotopes. The pre-ore Py1 is characterized by the lower ore element (Au, As, Sb, Cu and Ag) contents (mostly below the LA-ICP-MS detection limit) and Co/Ni ratios (average 0.31) than the ore-stage pyrites (Py2 and Py3), implying a sedimentary/diagenetic origin. The Py2 and Py3 have elevated ore element abundance (maximum As ​= ​6500 ​ppm, Au ​= ​22 ​ppm, Sb ​= ​6300 ​ppm, Cu ​= ​951 ​ppm, Ag ​= ​77 ​ppm) and Co/Ni ratios (average 1.84), and have positive As vs. Au–Sb–Cu–Ag correlations. Early-ore Stb1 has lower As (0.12–0.30 ​wt.%) than late-ore Stb2 (0.91–1.20 ​wt.%). These features show that the progressive As enrichment in ore sulfides is accompanied by increasing Au, Sb, Cu and Ag with the hydrothermal evolution, thereby making As a good proxy for Au. As-rich, As-poor and As-free zones are identified via NanoSIMS mapping of the Au-bearing pyrite. The As-rich zones in the Qinglong Au-bearing pyrites (Py2 and Py3) and ore stibnites (Stb1 and Stb2) have narrow δ 34 S H 2 S ranges (−8.9‰ to +4.1‰, average −3.1‰) and −2.9‰ to +6.9‰, average ​+ ​1.3‰), respectively, indicating that the Au-rich and Sb-rich fluids may have had the same sulfur source. Published in-situ sulfur isotopic data of pyrite As-rich zones from other Carlin-like Au deposits (Shuiyindong, Taipingdong, Nayang, Getang and Lianhuashan) in the NWYB have similar ore-fluid δ S H 2 S 34 values (−4.5‰ to +6.7‰, average −0.6‰) to those of Qinglong. Therefore, we infer that the sulfur of both Au and Sb mineralization was derived from the same magmatic-related source (0 ​± ​5‰) in the NWYB. Moreover, the core of pyrites (Py1) has variable S isotope fractionation (−18.9‰ to +18.1‰, mostly +3‰ to +12‰), suggesting that the higher-34S H2S was produced by bacterial sulfate reduction (BSR). The hydrothermal pyrite (Py2 and Py3) δ34S values gradually decrease with increasing As concentrations, and ultimately, within the restricted range (−5‰ to +5‰) in As-rich zones. This variation implies that the As-rich pyrite was formed through ongoing interactions of the magmatic-hydrothermal fluid with pre-existing sedimentary pyrites, causing the progressive decreasing δ34S values with As content increase, Hence, the fluid/mineral interaction may have generated the observed variation in δ34S and As contents. Overall, comparing the Au and Sb deposits in the NWYB, we favor a magmatic-related source for the Au–Sb–As-rich fluids, but the Au- and Sb-ore fluids were likely evolved at separate stages in the ore-forming system.

The Coastal Cordillera metallogenic province of northern Chile comprises several styles of mineralization, including stratabound Cu–(Ag), iron oxide–copper–gold (IOCG), iron oxide–apatite (IOA), an...

High sensitivity laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) has been utilized for the determination of trace elements in pyrite from the Tharsis VMS deposit, one of the most significant volcanogenic massive sulphide deposits in the southern Iberian Pyrite Belt. The study tracks the content and distribution of trace elements within the different facies of massive sulphides. Widespread and variable enrichment in elements such as Cu, Zn, and Pb in pyrite is interpreted to be due to the presence of nanoinclusions of chalcopyrite, sphalerite, and galena, respectively. A second group of elements, including As, Au, Tl, Mn and Mo, shows significant chemical variations according to the type of mineralization and the textural evolution of the pyrite. This behaviour is thought to be due to the fact that these metals are included in the mineral lattice and its incorporation is controlled by the degree of crystallinity, the temperature, and the redox conditions during crystallization. Early, spongiform and colloform pyrite in the stockwork is enriched in As and Au and interpreted to have formed from a high temperature and low fS2–fO2 fluid. Thallium, Mn, and Mo are enriched in pyrite precipitated at lower temperature and higher oxidation state, i.e., in the exhalative part of the system or in distal facies to the hydrothermal vents. In general, both Co and Ni show an irregular distribution and do not have the sympathetic distribution observed in equivalent studies.

Geochemical mapping using stream sediments from MRDB, north-central, Nigeria was undertaken towards obtaining multivariate association patterns reflecting the presence of ore mineralization in Lokoja region. The area is underlain by Precambrian crystalline rocks within the Benin-Nigeria Shield and clastic sedimentary rocks of Bida Basin (one of Nigeria inland sedimentary basins). The basement crystalline rocks have been known as a source of ore minerals in Nigeria. The major lithological units are cut by the Meme river watershed which have deposited in their tributaries, large quantities of alluvial and eluvial deposits formed during an extensive period of weathering and surficial processes. The PC analysis was performed on clr-transformed of Meme sediment geochemical compositional data of selected ore forming elements in the hope of obtaining geochemical information that could elucidate on the inferred ore mineralization of the region. The eight PCs explain about 93% of the total variance. The positive and negative loadings of PCs indicated the presences of oxides, sulphides, REEs and gems mineralisation in the region. Further interrogation of Spearman correlation of ilr transformed data with respect to the PC loadings indicated  well developed relationship between Sr and V (0.55), Mn and Pb (0.89), Mn and Ta (0.77), Mn and Nb (0.78), Nb vs Ta (0.98), Rb and Cr (0.59), In and As (0.64), Pb and Ga (0.78), Sb and Au (0.52), Ba and Cr (0.50). The elemental association suggests that they are either indicator of their own mineralization or are suitable pathfinders to pertinent minerals in Lokoja region. The negative correlation between Fe with other ore elements indicated that the Fe is from both proximal and dextral sources probably due to many Fe formations and mineralisation (goethite, haematite± siderite – bearing sedimentary ironstone formations in the region). The high Spearman correlation coefficients between Mn, Nb and Ta inferred that these ore elements are from the proximal sources because they are reliable pathfinders to pertinent oxides mineralisation in the region. Inferred proximal mineralisation in the region include beryl, topaz, columbite, quartzofeldspathic and quartz veins with anomalous concentration of Au as well as industrial minerals which are artisanally mined in places for industrial purposes.Â

The Jiaodong Peninsula is one of the most important Au ore provinces in China. There is an ongoing debate on the correlation between ore formation and magmatism in this province, because few intrusive rocks exhibit a clear association with ore deposits. A mineralized biotite monzodiorite (BM) stock, with disseminated ore, pervasive phyllic alteration, and no deformation, was found in a borehole in the footwall of the Zhaoping fault within the Luanjiahe Au deposit, which may shed light on this debate. The biotite monzodiorite contains explosion breccias, miarolitic cavities, skeletal and dendritic quartz, and late-stage evolved aplite dikes, and the in-situ δ34S values of the disseminated pyrite which is associated with Au mineralization are −1.7‰ to 7.3‰ (mean=3.5‰), indicative of a magmatic-hydrothermal system. These findings, combined with the reported age of 123 Ma, show that the intrusion has close spatial, temporal, and geochemical relationships with Au mineralization in the area. The biotite monzodiorite is metaluminous, high-K calc-alkaline and shoshonitic, with enrichment in light rare earth elements (REEs) and large-ion lithophile elements (LILEs), depletion in high-field-strength elements (HFSEs), and enriched Sr-Nd isotopic compositions. The intrusion may be the product of partial melting of enriched lithospheric mantle with a small lower crustal component. The hydrous, Au-bearing, enriched mantle source, and the strongly oxidized magma that was generated, created favorable conditions for Au mineralization.

The Aqishan-Yamansu metallogenic belt (AYMB) in East Tianshan hosts abundant submarine volcanic-hosted iron deposits. Although there is agreement with the magmatic source of the ore-forming materials and the role of hydrothermal replacement in iron ore formation, the mineralization processes of these iron deposits remain uncertain. Three ore types are identified on the basis of the geological occurrences of minerals and the sequence of mineral in ores. The type I ores are characterized by magnetite, diopside, amphibole with a few pyrite, and chalcopyrite. The type II ores are mainly composed of magnetite, garnet, chlorite with a few pyrite, while the type III ores are mainly composed of magnetite, quartz, calcite with a few pyrite. In order to constrain the mineralization processes of these ore types, we performed iron isotopes and trace element compositions of magnetite from three typical iron deposits (Yamansu, Duotoushan and Luotuofeng). Trace element and Fe isotope investigations of the three ore types reveal two major groups. The group I consists of analyses of the type I and II ores, with both showing a narrow range of positive δ56Fe values (+0.08‰ to +0.22‰ for type I ores and +0.15‰ to +0.22‰ for type II ores) and plotting in the range of the ortho-magmatic field. In contrast, the group 2 is composed merely of the type III ores, showing a wider range of negative δ56Fe values (-0.49‰ to -0.01‰), which is similar to the features of Fe-skarn magnetite. As shown in the binary diagrams of magnetite trace elements and a fractionation of the Fe isotopes, different ore types were likely produced during gradually changing ore-forming stages from magmatic to hydrothermal. Collectively, the submarine volcanic-hosted iron deposits in the East Tianshan are likely the results of a continuous magmatic-hydrothermal mineralization process.

Large-scale gold mineralization during the Early Cretaceous is identified in the Jiaodong Peninsula of China. Sources of ore-forming fluids remain debated. We study the Qilishan gold deposit in the northwestern Jiaodong Peninsula with detailed mineralogical observation and in-situ sulfur isotope analyses, in order to reveal the gold occurrence and the origin of ore-forming fluids. The Qilishan gold deposit is mainly clastic altered rock-type in mineralization, and ore minerals are visible native gold, electrum, pyrite, chalcopyrite and galena, gangue minerals as quartz, sericite and calcite. The gold occurrence includes inclusion and intergranular types, formed within pyrites and chalcopyrites and along their fissures. In-situ sulfur isotope analysis of gold-bearing sulfides suggests that the Qilishan deposit is enriched in heavy sulfur, with δ34S values mainly from +8.0‰ to +12.0‰. δ34S values increase gradually with the fluid evolution from the early to late stages, which is interpreted to be related to the loss of sulfur via sulfide precipitation. The crystallization of sulfides from hydrothermal fluids may have triggered the instability of Au(HS)2, and finally led to gold precipitation. Combined with sulfur isotope compositions of other gold deposits (n=43) and wall-rocks in the Jiaodong Peninsula, it is proposed that the ore-forming fluids were probably not directly originated from metamorphic wall-rocks (e.g., Jiaodong Group). Moreover, the relatively long time interval rules out the possibility that the gold mineralization (ca. 120 Ma) was associated with granitic magma activities (mostly 160–150 Ma). Possible ore genesis scenario is that, long-term subduction of slabs (e.g., the Paleo-Pacific) with gold-enriched pyritic materials and crustal sedimentary rocks resulted in both high Au contents and positive δ34S values of sulfur in the lithospheric mantle below the North China Craton. Subsequently, devolatilization of the metasomatized mantle produced auriferous fluids that migrated upward along translithospheric fault systems, and gold finally precipitated in favorable structural positions, generating the world-class Jiaodong deposits in the Early Cretaceous.

U-Pb dating of cassiterite and zircon from the Yazov granite (Transbaikalia region, Eastern Siberia, Russia) and cassiterite from spatially associated tin mineralization in the Tuyukan ore district in the Tonod uplift was conducted using in situ laser ablation inductively coupled plasma mass spectrometry. These analyses allow comparison of isotopic systematics for both minerals, especially related to transport in granitic magma. These data are also useful for understanding possible genetic links between the granite and the tin mineralization. Most of the U-Pb zircon analyses define a 206Pb/238U age of 719 ± 15 Ma for the granite; in addition, several zircon cores define an inheritance age of 1839 ± 21 Ma. U-Pb data for 10 nearly concordant analyses of disseminated cassiterite from the same samples yield a 206Pb/238U age of 1838 ± 34 Ma. This is the first documented evidence of cassiterite inheritance in granitic magma. These data indicate the robust character of U-Pb isotope systematics in cassiterite, comparable to that in zircon. The presence of numerous inclusions of cassiterite in zircon from the Yazov granite (revealed by nanotomography) supports the interpretation of inherited cassiterite included during Neoproterozoic zircon crystallization. The data indicate that high tin concentrations in the Yazov granite are due to the incorporation of older cassiterite crystals from country rock, not coeval cassiterite crystallization. Cassiterite samples from two ore occurrences spatially associated with the Yazov granite yield Pb-Pb isochron ages of 1.86–1.82 Ga, indicating that tin mineralization occurred in the Paleoproterozoic, nearly 1 Ga before emplacement of the Yazov granite. Tin mineralization of the ore region is probably related to ~ 1.85 Ga Chuya-Kodar tin-bearing granitic rocks that host tin deposits. These results have broad implications for understanding how critical elements, such as tin, may become enriched in rare-metal granites and how they are related to regional to global geodynamic processes.

The W Horizon is a thin continuous zone of low sulfide-high-grade platinum group element (PGE) mineralization in the Two Duck Lake gabbro at the Marathon Cu-PGE deposit, Coldwell Complex, Canada, that resembles reef-type PGE deposits found in much larger intrusions. The Marathon deposit was previously shown to have grown by accretion of syn-magmatic, sulfide-bearing sill-like intrusions that formed each of the W Horizon, Main Zone, and Lower Zone mineralization. Each zone can be distinguished by features such as sulfide mineral or platinum group mineral assemblages, or by Cu/Pd, Pd/Se, and Pd/Au values. For example, the W Horizon is defined by the presence of bornite, very high PGE values, low Cu/Pd ( 95% of the original sulfide liquid. In some samples, metal and S abundances indicate that PGE were transported as TABS-PGE phases. This work describes an example of thin PGE-rich sill-like injections that could be of importance to PGE exploration elsewhere.

Sheytoor Iron Ore deposit is located in Yazd province of Iran (Bafq). The most abundant ore is magnetite, which can be seen in the form of mass and granular tissue in various forms of self-shaped, semi-self-shaped and amorphous. The main purpose of this study is to identify the geochemical relationship of phosphorus and sulfur elements and also three-dimensional modeling of mineralization of these elements in iron ore. In order to achieve the research goal, methods such as k-mean clustering technique, concentration-volume fractal as well as block modeling with kriging estimator and Inverse Distance Weighting (IDW) interpolator were used. The model of geochemical behavior of phosphorus and sulfur elements compared to iron is of great importance because these two elements are known as deleterious elements in mineral processing and steelmaking processes, which are the post-mining stages. Existence of geochemical model and identification of elements’ behavior towards each other play a key role in optimizing mining operations in order to achieve geometallurgical goals. The results of this study are the three-dimensional model of mineralization of iron, phosphorus and sulfur elements, separation of phosphorus and sulfur mineralization communities and also presenting the model of enrichment community of these two elements. All the results are in line with geometallurgical studies and can optimize the next steps by optimizing the mining process.

松山锡矿位于滇西临沧花岗岩基的西北侧。矿体主要赋存于临沧黑云母二长花岗岩与松山组绢云石英片岩接触带矽卡岩，以及花岗岩和围岩的裂隙中。由于缺乏精确的成矿年代学数据，在一定程度上限制了对矿床成因的认识，并制约了进一步的找矿勘查工作。本文首次利用LA-SF-ICP-MS微区原位U-Pb同位素测年技术，对松山锡矿床矽卡岩型和电气石石英脉型矿石中的锡石矿物开展了U-Pb年代学研究，获得2件锡石样品的207Pb/206Pb-238U/206Pb谐和年龄分别为76.6±1.5Ma和79.6±3.6Ma，说明松山锡矿锡的成矿作用主要发生在晚白垩世，与临沧花岗岩主体侵位时间（三叠纪）明显不同。结合地质特征和前人年代学研究成果，本文认为该地区存在明显的晚白垩世锡的成矿事件，研究区下一步的找矿工作应围绕岩体与围岩接触带，以及岩体和围岩中的断裂展开。

The Burgali deposit is located in the Paleozoic Kedon volcanic belt (KVB) within the Omolon cratonic terrane. The orebodies of the Burgali deposit are veined and stockwork-type. The studies of the wallrock metasomatites demonstrate that the erosional truncation of the deposit is close to minimal. The ores of the deposit are enriched in the chalcophile elements (Au, Ag, As, Sb, Te, W, Mo, and Bi) and poor in the rare earths. The rare-earth element (REE) spectra are dominated by light lanthanides. The ores are characterized as very low-sulfidation with finely disseminated mineralization, widespread occurrence of chalcedony, and widespread colloform-banded, often combined with brecciated, structures. The late quartz veins contain Lower Carboniferous coaly siltstone fragments, filled with petrified timber remains, which indicate the Carboniferous age of the ore mineralization. The ores contain widespread Au- and Te-bearing pearceite and rare minerals such as argyrodite and the selenous petrovskaite and uytenbogaardtite. The data obtained enable the Burgali deposit to be classified as low-sulfidation epithermal. The outlook for Ag and Au reserve additions is based on the further studies and exploration of the ore-bearing stockwork.