Geochemical evolution of micas and Sn-, Nb-, Ta- mineralization associated with the rare metal pegmatite in Angwan Doka, central Nigeria

AbstractQuartz-diorites, monzogranites and pegmatites are the main rock units in the studied area. The pegmatites occur as zoned pockets within monzogranites with zonal arrangement: border, wall, intermediate, and core zones. The wall zone have enrichment of radioactive and RREs-bearing minerals. K-feldspar, plagioclase and quartz are essential minerals, whereas uranothorite, columbite, zircon, xenotime, monazite, sphalerite and pyrite are accessories. Geochemically, the pegmatites of W. Ghadir have peraluminous character, ferroan with alkalic–calcic affinity and emplaced in within plate setting. These pegmatites revealed Li-bearing variety and high level of rare earth elements mineralization. The studied pegmatites exhibit high contents of Li, Nb, Cu, Ta, U, Th, Pb, Zr, Zn and Ga, can be from the previous data, the studied pegmatites can be classified as a Niobium–Yttrium–Fluorine (NYF) pegmatite or rare metal pegmatite. The trace elements ratio supports a low degree of fractionation and metasomatism in the evolutionary history of the pegmatites, and the very low Cs values (2.2–4.3 ppm) indicate paucity of alkali metal fractionation. Spectrometric investigation revealed that monzogranites are not uraniferous, while the radioactive anomaly is confined to the pegmatites. Applying the U mobilization equation proved that pegmatite samples have been originated from a late magmatic phase of magma very rich in radioelements, and the pegmatites affected with hydrothermal solutions rich in uranium than thorium which indicates uranium addition. Radioactive and important heavy minerals are represented by uranothorite, columbite, zircon, monazite, xenotime, sphalerite and pyrite.

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Petrogenetic and Compositional Features of Rare Metal Pan-African Post-Collisional Pegmatites of Southwestern Nigeria; A Status Review

Contemporary Trends in Geoscience ◽

10.2478/ctg-2018-0012 ◽

2018 ◽

Vol 7 (2) ◽

pp. 166-187

Author(s):

Abiola Oyebamiji ◽

Adeniyi JohnPaul Adewumi ◽

Tehseen Zafar ◽

Adegbola Odebunmi ◽

Philips Falae ◽

...

Keyword(s):

Mineral Chemistry ◽

Rare Metal ◽

Border Zone ◽

Chemical Compositions ◽

Molten Material ◽

Southwestern Nigeria ◽

Pan African ◽

Opening And Closing ◽

High Degree ◽

Rare Metal Pegmatite

Abstract This research reviews the geology, petrogenesis, compositional trends and geochronology of the rare-metal pegmatite of southwestern Nigeria. The source of these pegmatites is still presently debated which have been explained as either product of highly fractionated molten material or anatexis of the local crust. However, published works of past authors have been compiled to give a detailed understanding of the formation of the mineral deposits. The basement complex of southwestern Nigeria comprises of Precambrian rocks of amphibolite, the hornblende gneiss and the granite gneisses which were formed as a result of the opening and closing of the ensialic basin with significant, extensive subduction during the Pan-African orogeny. The pegmatites in this region have shown internal zoning and a high degree of evolution from the border zone to the core zone during the crystallization and solidification of the felsic granite to pegmatite melt. The rare-metal pegmatites have distinct chemical compositions and mineralogy, containing quartz, biotite, muscovite, microcline, garnet with localized tourmaline, tantalite and columbite. These pegmatites vary significantly by their bulk-rock and mineral chemistry which indicates a more peraluminous attribute and enrichments of lithophile elements of Rb, Cs, Ta and Ba. Previous K/Ar isotopic ages (502.8±13.0 Ma and 514.5±13.2 Ma) suggest that the pegmatites are related to the post-collisional phase of intensive metasomatism. Adopted from previous studies, a five-stage conceptual model of evolution which is widely accepted have been proposed for the origin of the pegmatites.

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Paragenesis of Li minerals in the Nanyangshan rare-metal pegmatite, Northern China: Toward a generalized sequence of Li crystallization in Li–Cs–Ta-type granitic pegmatites

American Mineralogist ◽

10.2138/am-2022-8285 ◽

2022 ◽

Keyword(s):

Northern China ◽

Rare Metal ◽

Granitic Pegmatites ◽

Rare Metal Pegmatite

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Zircon as a Mineral Indicating the Stage of Granitoid Magmatism at Northern Chukotka, Russia

Geosciences ◽

10.3390/geosciences10050194 ◽

2020 ◽

Vol 10 (5) ◽

pp. 194

Author(s):

Viktor I. Alekseev ◽

Ivan V. Alekseev

Keyword(s):

Morphological Evolution ◽

Rare Metal ◽

Geochemical Evolution ◽

Gradual Change ◽

Granitoid Magmatism ◽

Mineral Inclusions ◽

Rare Elements ◽

Multi Stage ◽

Magmatic Stage ◽

Cretaceous Magmatism

A comparative study of the zircon composition and texture in granites of a three-stage Late Cretaceous magmatism in the Chaun area, Chukotka, Russia, was conducted in biotite granites (BG), quartz monzonites-monzogranites (MG), and zinnwaldite granites (ZG). The significance of the study entails determining the mineralogical indicators of similar granitoids in areas of multi-stage petrogenesis. It is shown that in the rock series of Northern Chukotka, BG → MG → ZG, a morphological evolution of zircon takes place: a reduction in size, elongation, a growing complexity of the crystallography, and an individual texture. In later generations of zircon, as a result of the recrystallization and metasomatism, rare-metal overgrowths, defects in the crystal structure, pores and fissures, and mineral inclusions appear, whereas the crystal-face indices and patterns become more complicated. We can observe the geochemical evolution of zircon: a gradual change in the concentration of trace elements (Hf, U, Y, Th, Nb, and Ti), rare earth elements (Yb, Er, and Dy, as well as Ce and Nd), and uncommon elements (Ca and Al). Rare elements (REE, Y, Hf, Nb, U, and Th) at the post-magmatic stage of the regional history acquired economic abundances. Zircon is therefore indicative of productive ore-magmatic systems.

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Rare-Metal Pegmatite Deposits of the Kalba Region, Eastern Kazakhstan: Age, Composition and Petrogenetic Implications

Minerals ◽

10.3390/min10111017 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1017

Author(s):

Sergey V. Khromykh ◽

Tatiana A. Oitseva ◽

Pavel D. Kotler ◽

Boris A. D’yachkov ◽

Sergey Z. Smirnov ◽

...

Keyword(s):

Phase 1 ◽

Rare Metal ◽

Rare Metals ◽

Geochronological Data ◽

Age Composition ◽

Deep Faults ◽

Mineral Assemblages ◽

Rare Metal Pegmatite ◽

Ore District ◽

Eastern Kazakhstan

The paper presents new geological, mineralogical, and isotope geochronological data for rare-metal pegmatites in the Kalba granitic batholith (Eastern Kazakhstan). Mineralization is especially abundant in the Central-Kalba ore district, where pegmatite bodies occur at the top of large granite plutons and at intersections of deep faults. The pegmatites contain several successive mineral assemblages from barren quartz-microcline and quartz-microcline-albite to Li-Cs-Ta-Nb-Be-Sn-bearing cleavelandite-lepidolite-spodumene. Ar-Ar muscovite and lepidolite ages bracket the metallogenic event between 291 and 286 Ma. The pegmatite mineral deposits formed synchronously with the emplacement of the phase 1 Kalba granites during the evolution of hydrous silicate rare-metal magmas that are produced by the differentiation of granite magma at large sources with possible inputs of F and rare metals with fluids.

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Age of the Dahongliutan rare metal pegmatite deposit, West Kunlun, Xinjiang (NW China): Constraints from LA–ICP–MS U–Pb dating of columbite-(Fe) and cassiterite

Ore Geology Reviews ◽

10.1016/j.oregeorev.2016.11.010 ◽

2018 ◽

Vol 100 ◽

pp. 561-573 ◽

Cited By ~ 21

Author(s):

Qing-He Yan ◽

Zeng-Wang Qiu ◽

He Wang ◽

Min Wang ◽

Xiao-Peng Wei ◽

...

Keyword(s):

Rare Metal ◽

Nw China ◽

Icp Ms ◽

West Kunlun ◽

Rare Metal Pegmatite

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GEOCHRONOLOGY OF LITHIUM-BEARING GRANITOIDS OF INGUL MEGABLOCK (UKRAINIAN SHIELD)

Visnyk of Taras Shevchenko National University of Kyiv Geology ◽

10.17721/1728-2713.82.03 ◽

2018 ◽

pp. 23-28 ◽

Cited By ~ 2

Author(s):

L. Stepanyuk ◽

O. Hrinchenko ◽

B. Slobodian ◽

V. Semka ◽

S. Kurylo ◽

...

Keyword(s):

Economic Development ◽

Rare Metal ◽

Ukrainian Shield ◽

Rare Metals ◽

Isotopic Method ◽

Metallic Mineral ◽

Level Of Economic Development ◽

Modern Level ◽

Marine Basins ◽

Rare Metal Pegmatite

Rare-metal elements are strategic metals which, in general, are extremely important for economic development or maintenance of defence capability of any country at the modern level. The list of needs for these strategic metals ranges depending on the level of economic development of certain country, but in general it includes such elements as Li, Ta, Nb, Be, Sb, W, REE and others. The majority of these elements has the lithophilous nature and, therefore, is characterized by close genetic relations with granites and pegmatites associated with them. In the world, industrial production of lithium is shared between deposits to lithium-bearing brine of saline depositions of marine basins (Argentina, Chile), some granites (China) and rare-metal pegmatites (Australia, China, Zimmbabve). In pegmatites lithium mineralization is represented mainly by spodumene (LiAlSi2O6), But other lithium-containing metallic minerals can also play an important role in production of this metal – petalite (LiAlSi4O10), minerals of lepidolite (Sa [Li,Al]3[Si,Al]4O10[F,OH]2) and amblygonite-montebrasite (LiAlPO4 [F,OH]) series. Rare-metal pegmatite of Ingul megablock of Ukrainian Shield can be treated as unique (insufficiently studied in world practice) pegmatitic formations in which the main metallic mineral is represented by petalite. In metallogenic interpretations two ore districts can be distinguished within the megablok, that are specialized on rare metals (Li, Rb, Cs, Be, Ta, Nb, Sn) – Polohivka and Stankuvatka. Deposits and numerous ore manifestations of rare metals formed in rather similar geological and tectonic conditions and have many common features – both country rocks composition and mineralogic composition of ores. Within Ingul megablock (Shpola-Tashlyk rare-metal district) a number of lithium rare-metal deposits associated with pegmatites is discovered. In order to determine the age of lithium mineralization in granites of Lypniazhka, Taburyshche massifs and vein bodies of pegmatitic and aplito-pegmatitic granites, which are selected from different localities of this megablock, are dated by U-Pd isotopic method by monazites. It is established that emplacement of vein granites of Ingul megablock occurred within rather narrow age interval – 2040-2020 Ma and it is not significantly separated in time from formation of most granitoids they are spatially associated with. This fact, together with geological evidences, gives grounds to make the assumption that rare-metal lithium pegmatite are formed in the same age interval.

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