Abstract. Götzenite and wöhlerite were found as part of a fissure assemblage in the Fohberg phonolite (Kaiserstuhl, SW Germany), in close association with natrolite and clinopyroxene (aegirine–augite). Crystal grains were separated and investigated by single-crystal X-ray diffraction (SXRD), electron probe microanalysis (EPMA), and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), showing the presence of two intimately intergrown phases, götzenite and wöhlerite. SXRD analyses showed that both minerals are twinned. Götzenite (Na1.50Ca5.18Sr0.13Fe0.032+Mn0.01Zr0.06La0.08Ce0.11Nd0.02Ti0.81Nb0.19(Si2O7)2O1.2F2.8) shows rotation twinning on [001] according to -a-1/2c, −b, c, with contributions of 40 % and 60 % from the two twin domains, respectively. Applying the twin law to the diffraction analysis, the crystal structure was refined to R1 (Fo >4σ (Fo)) = 3.0 %, with a=9.6191(3) Å, b=5.7342(2) Å, c=7.3386(2) Å, α=89.986(1)°, β=101.040(1)°, γ=100.485(1)°, and V=390.40(3) Å3 in space group P1‾. Wöhlerite (Na1.63Ca4.37Sr0.04Zr0.63Fe0.232+Mn0.09Ce0.01Ta0.01Nb0.79Ti0.20(Si2O7)2O2.6F1.4) shows reflection twinning on (100) according to -a-c, b, c, with contributions of 31 % and 69% from the two twin domains, respectively, and with lattice parameters of a=10.842(1) Å, b=10.249(1) Å, c=7.2673(8) Å, β=109.343(4)°, and V=761.9(2) Å3 in the monoclinic space group P21, refined to R1 = 1.3 %. Refractive indices of götzenite were measured using the immersion method yielding nx=1.662(2), ny=1.663(2), nz=1.670(2), and 2V=61(2)°. Optical measurements on the twinned crystal were possible because of the coincidence of the two indicatrices related to each other by rotation about nx being parallel to [001], simulating a unique extinction behavior. Wöhlerite could not be optically examined because of the polysynthetic twinning not showing this effect.

Abstract Ferroinnelite, Ba4Ti2Na(NaFe2+)Ti(Si2O7)2[(SO4)(PO4)]O2[O(OH)], is a new mineral from the Phlogopite deposit, Kovdor alkaline massif, Kola Peninsula, Russia. In an agpaitic pegmatite, ferroinnelite occurs as transparent elongated platy to tabular crystals up to 0.15 mm long. Associated minerals are cancrinite, orthoclase, aegirine–augite, magnesio-arfvedsonite, golyshevite and fluorapatite. The mineral is yellow to yellow brown with a vitreous lustre and a white streak, Dcalc. is 4.088 g/cm3. Ferroinnelite is triclinic, space group P $\bar 1$ , a = 5.3994(8), b = 7.09239(13), c = 14.7345(4) Å, α = 98.4086(19), β = 94.3275(18), γ = 90.0133(13)°, V = 556.56(8) Å3. The chemical composition of ferroinnelite is SO3 5.47, Nb2O5 0.45, P2O5 4.59, ZrO2 0.13, TiO2 16.91, SiO2 17.55, Al2O3 0.06, BaO 42.83, SrO 1.01, FeO 3.34, MnO 0.97, CaO 0.09, MgO 0.64, K2O 0.01, Na2O 4.47, H2O 1.11, F 0.15, O = F –0.06, total 99.72 wt.%, with H2O calculated from structure refinement. The empirical formula calculated on 26 (O + F) apfu is (Na1.95Fe2+0.64Mg0.21Mn2+0.19Ca0.02)Σ3.01(Ba3.84Sr0.13Na0.03)Σ4.00(Ti2.91Nb0.05Al0.02Zr0.01Mg0.01)Σ3.00Si4.02S0.94P0.89H1.70O25.89F0.11, Z = 1. The crystal structure was refined to an R1 index of 7.45% from 4485 unique reflections (Fo > 4σF). The structure is a combination of a TS (Titanium Silicate) and an I (intermediate) blocks. The TS block consists of HOH sheets (H – heteropolyhedral and O – octahedral). The O sheet is composed of Ti-, Na- and (Na,Fe2+)-octahedra, the H sheet, of [5]Ti-polyhedra and Si2O7 groups. The I block contains T sites, statistically occupied by S and P, and Ba atoms. Ideal compositions of the TS and I blocks are {Ti2Na(NaFe2+)Ti(Si2O7)2O2[O(OH)]}3– and {Ba4[(SO4)(PO4)]}3+. Ferroinnelite is a new member of the lamprophyllite group of the seidozerite supergroup. It is isostructural with innelite-1A, Ba4Ti2Na(NaMn2+)Ti(Si2O7)2[(SO4)(PO4)]O2[O(OH)]. Ferroinnelite and innelite are related by the following cation substitution at the MO3 site in the O sheet: Fe2+fer ↔ Mn2+inn. IR and Raman spectroscopies confirm presence of OH and H2O groups in ferroinnelite and innelite.

Abstract The Diely occurrence of metamorphosed As-rich manganese mineralisation is located in the Spišsko-gemerské rudohorie Mountains near the Poráč village and comprises Early Palaeozoic metamorphic rocks of the Gemeric Unit in the Western Carpathian region. Mineralisation is situated in the narrow tectonically delineated belt of Rakovec Group rocks consisting of mafic metavolcanic material generated during the back-arc submarine volcanic activity of the Early Ordovician–Silurian period. The Mn mineralisation is hosted in siliceous laminated lenses (metacherts) embedded in metabasalts and its tuffs. Manganese ore consists of quartz, braunite, rhodonite, nambulite, rhodochrosite, kutnohorite, OH-bearing garnets with dominant andradite composition, hematite, aegirine, aegirine–augite, ferri-ghoseite, ferri-winchite, baryte and pyrophanite. The mineralisation is cross-cut by a system of narrow younger veins composed dominantly of As-enriched minerals of the pyrosmalite group (schallerite, mcgillite and friedelite), tiragalloite, manganberzeliite, brandtite, sarkinite and svabite, associated with hematite, rhodochrosite, kutnohorite, baryte and quartz. Formation of manganese mineralisation at the Diely occurrence was caused by migration of seawater into the basaltic oceanic crust where increasing temperatures and acidity generated hydrothermal fluids enriched in manganese. The Mn-bearing hydrothermal fluids were enriched in Li, providing an additional substituent in the mineralisation. Following initial stages, the subsequent Variscan and Alpine tectonometamorphic events resulted in formation of three main mineralisation stages distinguishable by paragenetic relations and the mineral composition. Based on metamorphic association and amphibole geobarometric calculations, the peak metamorphic conditions reached was upper greenschist facies. The Diely occurrence near Poráč represents a unique metamorphosed manganese mineralisation with abundant arsenates and arsenosilicates previously unknown in the Western Carpathian region.

The Monte de Trigo Alkaline Suite is a Late Cretaceous syenite–gabbroid occurrence from the Serra do Mar Alkaline Province, southeastern Brazil. It has a zoned nepheline syenitic stock with nepheline syenite I (NSI), the most SiO 2 -undersaturated, in the centre, surrounded by nepheline syenite II (NSII) and alkali feldspar syenite with nepheline (SN). Synplutonic miaskitic and agpaitic nepheline microsyenite (MNM and ANM, respectively) dykes cut across the stock. Extensive fractionation of alkali feldspar and mafic minerals is attributed to the formation of the syenitic facies and dykes. Mineral chemical data indicate that SN crystallized at relatively high silica activity ( a SiO 2 ; 0.5–0.7), a H 2 O (0.24–0.11) and f O 2 (difference from the fayalite–magnetite–quartz buffer in log units, ΔFMQ + 0.2 to ΔFMQ − 0.2), in contrast to NSII and NSI ( a SiO 2 , ∼0.41; a H 2 O, 0.05–0.02; and f O 2 , ΔFMQ − 1.4 to ΔFMQ − 1.1). These parameters vary with magma evolution towards the phonolite eutectic and appear to control variations in paragenesis, from hastingsite + biotite ± diopside/hedenbergite in SN to hastingsite in NSII and hastingsite + hedenbergite in NSI. The MNM have high a H 2 O (0.31) and hastingsite + biotite + aegirine–augite assemblages. In contrast, the ANM are characterized by an F-rich anhydrous agpaitic assemblage.

Petrogenesis of the eudialyte-bearing syenite and indication for Nb-Zr-REE mineralization in Bashisuogong, Northwest China

An intensity tensor of quadrupole doublets and an electric field gradient tensor for Fe3+ at M1 sites in aegirine–augite ((Ca0.16Na0.86)∑1.02(Mg0.13Fe2+0.04Fe3+0.72 Al0.07)∑0.96Si2.01O6) are determined using single-crystal Mössbauer spectroscopy. The components of the intensity tensor are IXX = 0.670 (19), IYY = 0.353 (14), IXY = −0.113 (37) and IZZ = 0.477 (33). The components of the electric field gradient tensor (VXX, VYY and VZZ) for Fe3+ at M1 sites in aegirine–augite are −5.96 × 109, −4.65 × 1010 and 5.23 × 1010 C/m3, respectively. Comparisons of the intensity tensor of aegirine–augite with those of aegirine and augite (Wo40En45Fs16) that have already been reported and the IXX, IYY, IXY and IZZ intensity tensor components of aegirine–augite in this study are almost the same as those of aegirine, but different from those of augite. While the M2 sites of aegirine–augite and aegirine are fully occupied with Na+ and Ca2+ ions, the M2 sites of augite are not fully occupied with Ca2+. The compositional dependency of the intensity tensor components suggests that the intensity tensor components for Fe3+ at the M1 site of a solid solution between aegirine and augite are dependent on the occupancy of large cations such as Ca2+ and Na+ at M2 sites.

The destruction of the North China Craton (NCC) is a well‐known dynamic event in the Mesozoic, but the western NCC, with only few magmatic activities, has lacked studies so far. The Zijinshan alkaline complex, tectonically located at the western part of the NCC and the eastern edge of Ordos Block/Basin, is one of the most typical alkaline intrusions during the NCC destruction, and consists of monzonite, aegirine–augite syenite, nepheline syenite, pseudoleucite phonolite and trachyte porphyry. Geochronological, geochemical and in situ Sr–Nd–Hf isotopic analyses were performed on the various lithologies, in order to reveal the magma sources, petrogenesis and possible geodynamic processes. Zircon and titanite U–Pb dating shows that the Zijinshan complex was emplaced at ~130 Ma. The main rocks are enriched in light rare earth elements (LREEs) and large‐ion lithophile elements (LILEs; such as Rb, Ba, K, Sr), and depleted in heavy rare earth elements (HREEs) and high‐field‐strength elements (HFSEs; such as Th, U, Nb, Ta, Ti), without negative Eu anomaly. In addition, the obviously enriched and inhomogeneous Sr–Nd isotopic components occurred among the various lithologies, implying the primary magma of Zijinshan complex may originate from a deep mixed source. Specifically, the monzonites of Zijinshan complex come from the partial melting of the enriched lithospheric mantle with participation of crustal materials. Meanwhile, the nepheline syenites and alkaline volcanics originated from the enriched lithospheric mantle mixing with the depleted asthenosphere‐derived compositions. During the NCC destruction, continuous asthenospheric upwelling resulted in several times of mixing of melts from asthenospheric mantle, lithospheric mantle and lower crust in different proportions, and then the mixed magma of each episode migrated upward to the shallow part to form the Zijinshan pluton.

The North China Block and the South China Block collided in the Middle Triassic, but there is still a lack of consensus regarding the end of collisional orogeny and the closure time of the Paleo-Tethys. In this paper, we report zircon U–Pb ages and geochemistry for the Shimen pluton in the northern margin of the West Qinling Orogenic Belt to investigate its genesis and tectonic environment. The new findings allow to constrain the end time of the Triassic orogeny in the Qinling Orogenic Belt and the closure time of the Paleo-Tethys. The weighted average 206Pb/238U ages of the Shimen pluton are 218.6 ± 1.5 Ma and 221.0 ± 1.7 Ma. Thus, we suggest that the Shimen pluton crystallized at the 218.6 Ma and 221.0 Ma and was formed during the Late Triassic (Norian). The Shimen pluton is mainly syenogranite and has alkaline dark minerals aegirine–augite. It is composed of 73.45 to 77.80 wt.% SiO2, 8.28 to 9.76 wt.% alkali, and 11.35 to 13.58 wt.% Al2O3, with A/CNK ranging from 0.91 to 1.02 and 10,000 Ga/Al ranging from 2.39 to 3.15. These findings indicate that the Shimen pluton is typical A-type granite. The plutons have low rare earth element contents, ranging from 73.92 to 203.58 ppm, with a moderate negative Eu anomaly. All the samples are enriched in large-ion lithophile elements, such as Rb, Nd, Th and U, and light rare earth elements, and are depleted in high field strength elements, such as Nb, P, Zr, Ba, and Sr. The depletion of Ba, Sr, and Zr may be related to the fractionation and evolution of the granite. According to the petrological and geochemical characteristics, the Shimen pluton is an A1-type granite formed in an anorogenic extensional environment. Combined with its tectonic characteristics and petrogenesis, the Shimen pluton was probably formed by the partial melting of the crust under high temperature and low pressure in the intraplate environment after the subduction of the South China Block beneath the North China Block. This observation indicates that the Triassic orogeny in the Qinling Orogenic Belt had ended and the Paleo-Tethys-Mianlve Ocean had also closed by the Late Triassic (Norian).

Abstract Ferro-ferri-katophorite (IMA2016–008), ideally Na(NaCa)(Fe2+4Fe3+)(Si7Al)O22(OH)2, was found as xenocrysts up to 3 cm long and replacement rims around aegirine–augite in silicocarbonatite dykes cropping out in the Sierra de Maz, La Rioja province, NW Argentina. Ferro-ferri-katophorite is black and has vitreous lustre and a pale green streak. The new mineral is brittle, with perfect {110} cleavage and has a Mohs hardness of 6. The measured density is 3.32(1) g/cm3. In plane-polarised light it is strongly pleochroic, X = light greenish brown, Y = dark greyish brown and Z = dark greyish olive green. Absorption (very strong) is Z > Y > X. The orientation is: Z ∥ b, and X forms a small angle with [001]. Ferro-ferri-katophorite is biaxial (–), with α = 1.688(3), β = 1.697(3), γ = 1.698(3) and 2V(calc) = 36.7°. It is monoclinic, space group C2/m, a = 9.8270(7), b = 18.0300(8), c = 5.316(4) Å, β = 104.626(4)°, V = 911.4(6) Å3 and Z = 2. The strongest five lines in the powder X-ray diffraction pattern [d in Å (I)(hkl)] are: 8.416(100)(110), 3.135(50)(310), 2.815(26)(330), 2.720(18)(151) and 1.4422(15)($\bar{6}$61). The chemical composition is SiO2 43.08, TiO2 2.76, ZrO2 0.15, Al2O3 8.76, V2O3 0.07, Fe2O3 9.28, FeO 13.85, MnO 0.43, MgO 6.88, CaO 6.58, ZnO 0.06, Na2O 5.55, K2O 1.18, Cl 0.01, H2O calc 1.36, total 99.95 wt.%. The formula unit (confirmed by single-crystal structural analysis) is (Na0.74K0.23)Σ0.97(Ca1.08Na0.91Mn0.01)Σ2.00(Fe2+1.78Mg1.57Fe3+1.07Ti4+0.32Al0.19Mn2+0.04Zr0.01V3+0.01Zn0.01)Σ5.00(Si6.61Al1.39)Σ8.00O22(OH1.59O0.61)Σ2.00. Aluminium is strongly ordered at the T(1) site. Ferro-ferri-katophorite is the 9th species carrying the katophorite root name and is related to katophorite by the Fe2+ + Fe3+ → Mg2+ + Al3+ substitution. Type material was deposited at the Museo de Mineralogía “Stelzner”, Universidad Nacional de Córdoba, Argentina, under catalogue number MS003341.

Mineralogical characteristics and Sr–Nd–Pb isotopic compositions of banded REE ores in the Bayan Obo deposit, Inner Mongolia, China: Implications for their formation and origin

Stability conditions and compositional variations of deerite in high-pressure meta-ironstone during subduction–exhumation processes (SW Tianshan, China)

This paper reports the results of the first study of pyroxenes from the deepest zones of the Lovozero deposit. The geochemical and mineralogical study of these rocks is of great scientific interest, as they are the least differentiated rocks and provide insight into the composition of a parental magma. According to microprobe analysis, clinopyroxenes evolve from early diopside–hedenbergite–augite to later alkaline aegirine–augite species. Upsection, the contents of Na, Fe3+ and Ti increase, while Mg, Ca, Fe2+, and Zr decrease. Thus, isomorphic substitution in pyroxenes of the lower zone follows the scheme (Ca, Mg, Fe2+, Zr) → (Na, Fe3+, Ti).

Abstract The sodic amphibole glaucophane is generally considered as indicative of blueschist-facies metamorphism. However, sodic amphiboles display a large range in chemical compositions, owing principally to the Fe2+Mg–1 and Fe3+Al–1 substitutions. Therefore, the whole-rock composition (namely its Na2O and FeO* content, and the Fe2+–Fe3+ ratio), strongly controls the stability field of the sodic amphiboles at the transition from greenschist- to blueschist-facies conditions. Neglecting these variables can lead to erroneous estimates of the metamorphic conditions and consequently the tectonic framework of the rocks. This paper explores the mechanisms that control the development of sodic amphibole and sodic pyroxene within the basement of the Dent Blanche Tectonic System (Western Alps), as a result of the Alpine metamorphic history. Field, petrographic and geochemical data indicate that sodic amphibole and sodic pyroxene form in different rock types: (1) in undeformed pods of ultramafic cumulates (hornblendite), sodic amphibole (magnesioriebeckite) forms coronas around magmatic pargasite; (2) metatonalite displays patches of radiating sodic (magnesioriebeckite) and calcic (actinolite) amphiboles; (3) sodic amphibole (magnesioriebeckite–glaucophane) occurs with high-Si potassic white mica (phengitic muscovite) in fine-grained (blue) schists; (4) in mylonitized granitoids (amphibole-gneiss) metasomatized along the contact with ultramafic cumulates, sodic amphibole (magnesioriebeckite–winchite) mainly forms rosettes or sheaves, generally without a shape-preferred orientation. Only locally are the needles aligned parallel to the stretching lineation. Pale green aegirine–augite is dispersed in an albite–quartz matrix or forms layers of fine-grained fibrous aggregates. The bulk-rock chemical composition of the different lithologies indicates that sodic amphibole and sodic pyroxene developed in Na- and Fe-rich systems or in a system with high Fe3+/Fe*. Thermodynamic modelling performed for different rock types (taking into account the measured Fe2O3 contents) reveals that sodic amphibole appears at ∼8 ± 1 kbar and 400–450 °C (i.e. at the transition between the greenschist- and blueschist-facies conditions) about 5 kbar lower than previous estimates. To test the robustness of our conclusion, we performed a review of sodic amphibole compositions from a variety of terranes and P–T conditions. This shows (1) systematic variations of composition with P–T conditions and bulk-rock chemistry, and (2) that the amphibole compositions reported from the studied area are consistent with those reported from other greenschist- to blueschist-facies transitions.

Factors controlling the generation and diversity of giant carbonatite-related rare earth element deposits: Insights from the Mianning–Dechang belt

The Longwangzhuang pluton is a typical example of Paleoproterozoic A-type granite intrusions at the southern margin of the North China Craton. This pluton is composed of arfvedsonite granite and minor aegirine–augite granites. Samples from both granite types display similar zircon U-Pb ages with 207U-206Pb ages of 1612 ± 19 Ma [mean square weighted deviation (MSWD) = 0.66] and 1609 ± 24 Ma (MSWD = 0.5), respectively. The granites exhibit similar high silica (SiO2 = 71.1–73.4 wt.%), high alkaline (Na2O + K2O = 8.10–9.26 wt.%, K2O/Na2O > 1), and low Al2O3 (11.8–12.8 wt. %) contents and metaluminous to weakly peraluminous bulk chemistry. The chemical variations of the Longwangzhuang pluton suggest the effects of mineral fractionation. In addition, all samples show typical characteristics of A-type granites, such as high 10000Ga/Al ratios (4.10–7.28), high FeOtot/(FeOtot + MgO) ratios (0.88–0.99), and high Zr (484–1082 ppm), Ce (201–560 ppm), and Y (78–156 ppm) contents. The εNd(t) values and the (206Pb/204Pb)t, (207Pb/204Pb)t, and (208Pb/204Pb)t ratios of the arfvedsonite granite samples vary from −4.6 to –5.3, 15.021 to 17.349, 15.241 to 15.472, and 33.206 to 36.905, respectively, and those for the aegirine–augite granite sample amount at −0.2, 14.421, 15.175, and 33.706. The distinct and variable Nd and Pb isotope values indicate the presence of heterogeneous protoliths. Based on its geochemistry, its low initial Pb isotope ratios, and its enrichment in Nd isotopes, we infer that the Longwangzhuang A-type granite is the partial melting product of basement rocks such as the Taihua Group gneisses accompanied by some involvement of juvenile material from the mantle. Together with published data from other Paleoproterozoic A-type granite plutons exposed at the southern margin of the craton, our findings suggest that these granites had a similar origin. Furthermore, geochemically, they can be divided into two groups: A2-type, which formed earlier (~1.8–1.6 Ga), and A1-type, which formed later (~1.6–1.5 Ga). Combining this information with the variations in whole-rock Nd and zircon Hf isotopic composition at ca. 1.6 Ga, we propose that tectonic transformation from post-orogenic to anorogenic magmatism occurred at the southern margin of the North China Craton at that time.

Abstract The complete mineral description of potassic-magnesio-arfvedsonite, a recently approved (IMA2016-083) new species of the amphibole supergroup is provided using electron microprobe analysis (EMPA), laser ablation inductively coupled plasma mass spectrometry, single-crystal structure refinement, Mössbauer and Raman spectroscopy, as well as measurement of optical and physical properties. The holotype material was found in syenitic and granitic dyke rocks in association with quartz, potassium feldspar and aegirine–augite from the Buhovo–Seslavtsi pluton, Bulgaria. Potassic-magnesio-arfvedsonite is monoclinic C2/m, with unit-cell parameters: a = 9.9804(11), b = 18.0127(19), c = 5.2971(6) Å, β = 104.341(2)° and V = 922.61 Å3. In transmitted plane-polarised light (λ = 590 cm–1), potassic-magnesio-arfvedsonite is pleochroic: X = yellow pale-green, Y = green and Z = dark-violet brown. It is biaxial (–), α = 1.645(2), β = 1.655(2), γ = 1.660(2) and 2Vmeas. = 60° and 2Vcalc. = 70°. The empirical unit formula obtained from EMPA and structure refinement is A(K0.86Na0.0.08)0.94B(Na1.74Ca0.25 Mn2+0.01)2.00C(Mg2.67Fe2+1.42Fe3+0.76Ti0.12Mn2+0.03)5.00TSi8O22W(OH1.58F0.22O0.20)2.00. The Fe3+/Fetot ratio (0.35) is consistent with both the Mössbauer spectra and the single-crystal structure refinement. The 10 strongest X-ray powder reflections [d values (in A°), I, (hkl)] are: 8.519, 80.5, (110); 3.402, 67.3, (131); 3.295, 41.0, (240); 3.173, 65.0, (310); 2.752, 35.6, ( $\bar{3}$ 31); 2.715, 100.0 (151); 2.591, 44.1, (061); 2.542, 73.2, ( $\bar{2}$ 02); 2.348, 38.5, ( $\bar{3}$ 51); 2.174, 42.0, (261). Potassic-magnesio-arfvedsonite is the product of strongly peralkaline and potassic (perpotassic) magma compositions. Trace-element analysis shows that this amphibole did not exert significant control on trace-element distribution in the crystallising peralkaline magma.

The Qinling orogenic belt is a complex subduction–accretion–collision orogen that welded the North China Craton and the Yangtze Craton during the final continental collision in the Triassic. The Xiong'ershan area, located in east Qinling, exposes a typical Triassic syenite pluton and several contemporaneous Mo, Au, and Cu deposits. The aegirine–augite syenites and syenites from the Mogou pluton are characterized by alkalic to peralkalic (total alkali Na2O + K2O = 13.95–14.63 wt.%, CaO = 0.06–2.87 wt.%), and shoshonitic features (K2O = 11.86–14.34 wt.%). Zircon LA–ICP–MS U–Pb dating of the aegirine–augite syenite and syenite yield emplacement ages of 232.5 ± 0.6 and 221.8 ± 0.7 Ma, indicating multiple pulses of magmatism. Evidence from zircon Hf isotopes; occurrence of mafic microgranular enclaves; heterogeneous peralkaline composition; and wide ranges of MgO, Ni, and other trace elements suggest that the parental magma was mainly sourced from partial melting of Archean to Paleoproterozoic crustal sources, mixed with juvenile mantle‐derived mafic magmas. The Mogou pluton was probably emplaced in the tectonic transition from syn‐collision to post‐collision settings and accompanying slab break‐off process, from the commencement of collision at approximately 245 Ma and post‐collisional extension at approximately 210 Ma. Gold, molybdenum, and copper deposits formed during the interval of 255–208 Ma, and the close temporal and spatial relationship between these Triassic polymetallic deposits and the Mogou alkaline pluton invokes a genetic linkage. The heat source for magmatism and related metallogeny is correlated to a hot upwelling asthenospheric mantle that caused partial melting of the Archean to Paleoproterozoic crustal basement, resulting in magma mixing between the two end‐members.

Origin and paleoenvironment of Pleistocene–Holocene Travertine deposit from the Mbéré sedimentary sub-basin along the Central Cameroon shear zone: Insights from petrology and palynology and evidence for neotectonics

Titanite-bearing omphacitite from the Jade Tract, Myanmar: Interpretation from mineral and trace element compositions

Chemical and O-isotope compositions of amphiboles and clinopyroxenes from A-type granites of the Papanduva Pluton, South Brazil: Insights into late- to post-magmatic evolution of peralkaline systems