Beryllium Mineralogy of the Kola Peninsula, Russia—A Review

This paper reviews the available information on the beryllium mineralogy of the different type of occurrences in the Kola Peninsula, northwest Russia. Beryllium mineralization in the region is mainly associated with alkaline and felsic rocks, which differ significantly in petrological, geochemical, mineralogical features and age. In total 28 beryllium minerals are established on the Kola Peninsula up today. Beryl is one of the ore minerals in the differentiated granite pegmatites of the Kolmozerskoe lithium deposit. A large diversity of beryllium minerals occur in the pegmatites and hydrothermal veins formed in the late stages of the Lovozero and Khibiny alkaline massifs. Most of these minerals, as leifite, lovdarite, odintsovite, sphaerobertrandite and tugtupite are rare in other environments and have unique properties. These minerals formed under conditions of extreme alkalinity and their formation was favored by abrupt changes in the alkalinity regimes. Some of minerals, as chrysoberyl in xenoliths of hornfels, genthelvite and unique intergrowth of meliphanite and leucophanite formed in contrasting geochemical fronts between felsic/intermediate and mafic rocks.

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Minerály kontaminovaných granitových pegmatitů z lomu Pohled u Havlíčkova Brodu (moldanubikum), část II: prvky a sulfidy

Bulletin Mineralogie Petrologie ◽

10.46861/bmp.29.090 ◽

2021 ◽

Vol 29 (1) ◽

pp. 90-107

Author(s):

Zdeněk Dolníček ◽

Jana Ulmanová ◽

Karel Malý ◽

Jaroslav Havlíček ◽

Jiří Sejkora

Keyword(s):

Raman Spectrum ◽

Metamorphic Rocks ◽

Mineral Association ◽

Ore Minerals ◽

Ore Mineralization ◽

Mineralogical Study ◽

Native Bismuth ◽

Polymetallic Ore ◽

Hydrothermal Veins ◽

Cobalt And Nickel

In the Pohled quarry near Havlíčkův Brod town (central part of Czech Republic), texturally and mineralogically simple contaminated anatectic pegmatites form dikes or irregular bodies cementing breccia of host metamorphic rocks (paragneisses, amphibolites) belonging to the Monotonous (Ostrong) Group of the Moldanubicum of the Bohemian Massif. They exhibit signs of intense hydrothermal overprint and also the presence of abundant disseminations, nests and veinlets of ore minerals. A detailed mineralogical study revealed the presence of an extraordinary rich ore assemblage (20 species in total, including one unnamed phase). The oldest minerals are sphalerite (rich in Fe), löllingite, Fe-Co-Ni sulphoarsenides (cobaltite, glaucodot, arsenopyrite, gersdorffite), pyrrhotite, galena and chalcopyrite, in later portion accompanied by inclusions of Bi-minerals (native bismuth, bismuthinite, joséite-A, joséite-B, ikunolite and a Pb-Bi sulphosalt). The composition of the Pb-Bi sulphosalt is equal to Ag,Fe-substituted eclarite; its identity was confirmed also by Raman spectrum. Pyrite is very abundant phase, present probably in several generations. The Fe-Co-Ni thiospinels disseminated in younger chlorite, and represented by siegenite, violarite, grimmite and an unnamed NiFe2S4 phase, are the youngest ore minerals. The mineral association as well as chemical composition of most ore minerals are well comparable to those of local polymetallic ore veins and Alpine-type veins, which give evidence for identical origin of all these ore mineralizations. The formation of pegmatite-hosted ore assemblage was long-lasting multiphase process, which took place at temperatures between ca. 350 and <120 °C during changing fugacities of sulphur, tellurium and oxygen. A distinct enrichment in cobalt and nickel of ore mineralization hosted by pegmatites (in comparison with hydrothermal veins) is explained in terms of pronounced interactions of fluids with amphibolites and serpentinites.

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Mineralogická charakteristika křemenné žíly se scheelitem a alpské žíly s prehnitem z lomu v Plaňanech u Kolína (kutnohorské krystalinikum)

Bulletin Mineralogie Petrologie ◽

10.46861/bmp.28.074 ◽

2020 ◽

Vol 28 (1) ◽

pp. 74-85

Author(s):

Zdeněk Dolníček ◽

Jana Ulmanová

Keyword(s):

Host Rock ◽

Quartz Vein ◽

Crystalline Complex ◽

Host Rocks ◽

Felsic Rocks ◽

Hydrothermal Veins

Two new types of hydrothermal veins were found in the quarry at Plaňany. Both mineralizations are hosted by a lenticular body of amphibolites embedded in migmatites and gneisses of the Kutná Hora Crystalline Complex. The first type of mineralization is represented by subvertical scheelite-bearing quartz vein, which strikes WNW-ESE, perpendicularly to foliation planes of host rocks. In addition to quartz, the vein also contains a small amount of sulphides (especially chalcopyrite and molybdenite, less pyrite and sphalerite, rarely pyrrhotite and argentopentlandite), calcite, silicates [zoned amphibole (with compositions ranging from magnesiohornblende to actinolite), chlorite (clinochlore), plagioclase (andesine to albite) and prehnite] and scheelite, which forms up to 3 cm big nests in quartz. We cannot exclude the possibility that magnesiohornblende cores of amphibole crystals as well as andesine cores of plagioclases represent relics of host rock. Second type of mineralization is vein with prevailing prehnite, which is oblique to foliation of host amphibolites. Besides prehnite, it contains adularia, calcite and actinolitic amphibole. Both studied mineralizations represent retrograde-metamorphic mobilisates similar to the Alpine-type veins. Chlorite thermometry suggests that chlorite from scheelite-bearing quartz vein originated at temperatures between 253 and 298 °C. The source of Mo and W necessary for formation of molybdenite and scheelite is not clear, but one cannot exclude that these elements were transported by parent fluids from felsic rocks outside of the host amphibolite body.

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The ore minerals of the Ilímaussaq intrusion: their mode of occurrence and their conditions of formation

Bulletin Grønlands Geologiske Undersøgelse ◽

10.34194/bullggu.v127.6669 ◽

1978 ◽

Vol 127 ◽

pp. 1-51

Author(s):

S Karup-Møller

Keyword(s):

Chemical Composition ◽

Thermodynamic Data ◽

Phase Correlation ◽

Coarse Grained ◽

Bulk Chemical Composition ◽

Native Iron ◽

Ore Minerals ◽

Mode Of Occurrence ◽

Bulk Chemical ◽

Hydrothermal Veins

On the basis of their chemical composition, the Ilímaussaq ore minerals in pegmatites and hydrothermal veins have been subdivided into the following four associations: I Pb-Zn-Mo, II Cu-Sb (including two subtypes: IIA Cu-Sb and IIB Cu-Sb-S), III Fe-As and IV Fe-Ni-As-Sb. Accessory rock-forming ore minerals have been studied in heavy mineral concentrates isolated from the augite syenite and from the following agpaitic rocks: alkali granite, sodalite foyaite, naujaite, green lujavrite, medium- to coarse-grained lujavrite and black, red and white kakortokites. The ore minerals comprise sulphides (galena, sphalerite, molybdenite, pyrrhotite, troilite, marcasite, pyrite, chaIcopyrite and djerfisherite), native elements (tin, lead and iron), aIloys (seinäjokite [FeSb2] and unnamed Sn-Cu(-Pb)phase), arsenides (westerveldite and loeIlingite) and one antimonide (gudmundite). Oxides of iron, titanium and chromium have been identified. Native iron, native tin, unnamed Sn-Cu(-Pb)phase, decomposed wüstite and chromite may represent contaminated material. Some of the accessory rock forming ore minerals form two additional associations: V Fe-Cu and VI Fe-Ti-O. The accessory ore minerals in the agpaitic rocks crystallized relatively late compared to the silicate minerals. In the augite syenite the original pyrrhotite and associated chaIcopyrite crystallized from an immiscible sulphide phase. Correlation between accessory rock-forming ore minerals and bulk chemical composition of the major rocks is severely limited due to the lack of chemical data. The ore minerals in the rocks, pegmatites and veins crystallized at low sulphur and oxygen fugacities. The log αS2 and log fO2 ranges are semi-quantitatively estimated on the basis of published thermodynamic data.

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The field geology and petrography of the kofayi younger granite complex, central Nigeria

International Journal of Advanced Geosciences ◽

10.14419/ijag.v7i2.29055 ◽

2019 ◽

Vol 7 (2) ◽

pp. 95

Author(s):

Aga T ◽

Haruna A. I

Keyword(s):

Iron Oxide ◽

Mafic Magma ◽

Accessory Minerals ◽

Mafic Rocks ◽

North East ◽

Basement Rocks ◽

Ring Complex ◽

Granite Complex ◽

Field Geology ◽

Felsic Rocks

The Kofayi Younger Granite Complex is one of the several anorogenic alkaline Younger Granite Complexes that is located approximately 45 kilometres north east of Jos, Nigeria. The complex is found to comprise of felsic rocks like; biotite-granites, biotite microgranites and granodiorites. They are also found to be associated with mafic rocks like diorites which, at some portions have formed hybrid rocks. Quartz- feldspar- granites are the porphyritic rocks that found in the ring complex. The complex intrude the basement rocks of central Nigeria. Structural trends on these rocks suggest that they were controlled by some deep seated structures of the basement. Mineral suite identified include; fayalite, pyroxene, amphibole, k-feldspar, biotite, quartz, iron- oxide and accessory minerals like zircon, apatite, and allanite. Generally, the petrography of these rock samples reveal the presence of a mafic magma which has two pulses (a mafic and felsic pulse) of injection.

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The agpaitic rocks - an overview

Mineralogical Magazine ◽

10.1180/minmag.1997.061.407.02 ◽

1997 ◽

Vol 61 (407) ◽

pp. 485-498 ◽

Cited By ~ 94

Author(s):

Henning Sørensen

Keyword(s):

Rare Earth ◽

Gas Phase ◽

Water Soluble ◽

Main Stage ◽

Volatile Elements ◽

Rare Elements ◽

Late Stages ◽

Hydrothermal Veins ◽

Alkali Feldspars ◽

Postmagmatic Alteration

AbstractIt is now generally agreed that the term ‘agpaitic’ should be restricted to peralkaline nepheline syenites (and phonolites) containing minerals such as eudialyte and rinkite, that is complex silicates of Zr, Ti, the rare earth elements (REE), and F and other volatiles. There are, however, cases of transition into more common types of nepheline syenites containing zircon, titanite, ilmenite, etc.The agpaitic rocks are characterized by extremely high contents of rare elements such as Li, Be, Nb, Ta,REE, Zr, Th, etc. and of volatiles, first of all F and Cl. This gives rise to a wealth of mineral species, more than 500 in the Lovozero and Khibina complexes of the Kola peninsula, about 250 in Mont Saint-Hilaire, Quebec, Canada, and about 200 in the type locality, the Ilímaussaq complex, South Greenland.These rocks have very long melting intervals and solidus temperatures as low as 500 to 400°C. They are accompanied by a gas phase rich in methane and other hydrocarbons and most probably also by sodium-rich fluids as indicated by the presence of minerals such as ussingite (NaAlSi3O8·NaOH) and villiaumite (NaF) and of pegmatites and hydrothermal veins rich in sodium and rare and volatile elements.Agpaitic nepheline syenites are considered to have been formed by consolidation of melts oversaturated in alkalis, especially sodium, under conditions preventing the volatiles from escaping. These melts have been derived by extreme fractionation processes in alkali basaltic or nephelinitic magmas. The main stage of crystallization of the melts is characterized by minerals such as nepheline (sometimes also sodalite), alkali feldspars, arfvedsonite, aegirine and eudialyte, but the most highly developed, hyperagpaitic lujavrites of the Ilímaussaq complex have been formed from melts with extreme concentrations of sodium and volatiles resulting in the formation of naujakasite instead of nepheline, ussingite instead of sodalite and alkali feldspars, and steenstrupine instead of eudialyte. During the late stages of crystallization, sodium-rich fluids are the cause of late- and postmagmatic alteration and of the formation of hydrothermal mineralizations. The late stages are characterized by water-soluble sodium-rich minerals of which more than 80 have been found in the Khibina and Lovozero complexes.

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Paleoproterozoic layered PGE-bearing Monchetundra pluton, Kola Peninsula: Sm–Nd age of metamorphic alteration of mafic rocks

Doklady Earth Sciences ◽

10.1134/s1028334x15070181 ◽

2015 ◽

Vol 464 (1) ◽

pp. 885-888

Author(s):

E. L. Kunakkuzin ◽

P. A. Serov ◽

T. B. Bayanova ◽

L. I. Nerovich ◽

E. S. Borisenko

Keyword(s):

Kola Peninsula ◽

Mafic Rocks ◽

Metamorphic Alteration

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Ultramafic and Mafic Rocks Found in the Near Vicinity of Mariupolites within the Alkaline Oktiabrski Massif (SE Ukraine) – Preliminary Investigations

Gospodarka Surowcami Mineralnymi ◽

10.1515/gospo-2016-0015 ◽

2016 ◽

Vol 32 (2) ◽

pp. 63-78

Author(s):

Magdalena Dumańska-Słowik ◽

Wiesław Heflik

Keyword(s):

Mineral Composition ◽

Olivine Gabbro ◽

Magmatic Activity ◽

Calc Alkaline ◽

Mafic Rocks ◽

Alkaline Magma ◽

Preliminary Results ◽

South Eastern ◽

Two Generations ◽

Ore Minerals

AbstractThe preliminary results of the mineralogical and geochemical investigations of ultramafic (peridotite and pyroxenite) and mafic (olivine gabbro) rocks from the Mazurovski Field of the Oktiabrski Massif in South-eastern Ukraine are presented in this paper. Peridotite is mainly composed of olivine (forsterite), pyroxene (diallage), plagioclase (labradorite) and ore minerals such as magnetite, ilmenite and pyrite. Antigorite and talk are secondary components. Diallage with subordinate plagioclase, olivine and Fe compounds (oxides/sulphides) are found in pyroxenite. Gabro is made of two generations of plagioclase, diallage, olivine, biotite and amphiboles (hornblende and actinolite). Chlorite, talk and ore minerals (ilmenite, pyrite, Fe oxides/hydroxides) occur as its subordinate components. On the basis of their mineral composition peridotite was classified as wehrlite, pyroxenite as clinopyroxenite, whereas the mafic rocks are represented by olivine gabbro. The mafic rocks are most likely products orginating from calc-alkaline magma. Owing to the fact that chromite was not identified in periodite, it is very probable that this rock is loco-temperature differentation product of ultramorfic rocks. The ultrabasic rocks and enriched with Al2O3, CaO and Fe and complethy impoverished of REES and alkalis. Only one olivine gabbro shows some amounts of REEs (0.096 wt.% REEs with the distinct predominance of LREE over HREE) and alkalis (2.89–4.0 wt.% Na2O + K2O), which are surely genetically associated with alkaline rocks occurring in the near vicinity of the ultramafic and mafic rocks of the Oktiabrski Massif. The enrichment of gabbro in REEs and alkalis most probably proceeded post-magmatic activity.

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Synneusis: does its preservation imply magma mixing?

Mineralogia ◽

10.2478/mipo-2018-0009 ◽

2018 ◽

Vol 49 (1-4) ◽

pp. 99-117 ◽

Cited By ~ 2

Author(s):

Bibhuti Gogoi ◽

Ashima Saikia

Keyword(s):

Magma Mixing ◽

Mafic Magma ◽

Textural Features ◽

Magmatic Evolution ◽

Mafic Rocks ◽

Intermediate Rock ◽

Euhedral Crystal ◽

Mineral Compositions ◽

Felsic Rocks

Abstract The Ghansura Felsic Dome (GFD) occurring in the Bathani volcano-sedimentary sequence was intruded by mafic magma during its evolution leading to magma mixing. In addition to the mafic and felsic rocks, a porphyritic intermediate rock occurs in the GFD. The study of this rock may significantly contribute toward understanding the magmatic evolution of the Ghansura dome. The porphyritic rock preserves several textures indicating its hybrid nature, i.e. that it is a product of mafic-felsic magma mixing. Here, we aim to explain the origin of the intermediate rock with the help of textural features and mineral compositions. Monomineralic aggregates or glomerocrysts of plagioclase give the rock its characteristic porphyritic appearance. The fact that the plagioclase crystals constituting the glomerocrysts are joined along prominent euhedral crystal faces suggests the role of synneusis in the formation of the glomerocrysts. The compositions of the glomerocryst plagioclases are similar to those of plagioclases in the mafic rocks. The results from this study indicate that the porphyritic intermediate rock formed by the mixing of a crystal-rich mafic magma and a crystal-poor felsic melt.

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On the mineralogy and paragenesis of tugtupite Na8Al2Be2Si8O24(Cl,S)2 from the Ilímaussaq alkaline intrusion, South Greenland

Bulletin Grønlands Geologiske Undersøgelse ◽

10.34194/bullggu.v95.6635 ◽

1971 ◽

Vol 95 ◽

pp. 3-57

Author(s):

H Sørensen ◽

M Danø ◽

O.V Petersen ◽

A.S Povarennykh ◽

A.N Platonov ◽

...

Keyword(s):

Crystal Structure ◽

Kola Peninsula ◽

Alkaline Intrusion ◽

Hydrothermal Veins

Tugtupite, Na8Al2Be2Si8O24(Cl,S) 2, is colourless to red, tetragonal, pseudocubic and forms triplet twins on {101}. c: a = 1.0269 ± 0.0003, d = 2.33 g/cm3, nε = 1.499 ± 0.001, nα = 1.495 ± 0.001. a0 = 8.637-8.643, c0 = 8.867 - 8.870, V0 = 662 Å3. The description of the crystal structure is taken from Danø (1966). The mineral occurs in hydrothermal veins in the Ilímaussaq alkaline intrusion, South Greenland, and in the Lovozero alkaline intrusion, Kola Peninsula (beryllosodalite). A number of occurrences of tugtupite in Ilimaussaq are described. Tugtupite is most commonly associated with albite, analcime and Li-mica and is generally secondary after chkalovite. The paragenesis and origin of the mineral and a number of associated beryllium silicates are discussed.

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Late sodic metasomatism evidences in bimodal volcanic rocks of the Acampamento Velho Alloformation, Neoproterozoic III, southern Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652007000400012 ◽

2007 ◽

Vol 79 (4) ◽

pp. 725-737 ◽

Cited By ~ 2

Author(s):

Delia Del Pilar M. de Almeida ◽

Vitor P. Pereira ◽

Adriane Machado ◽

Henrique Zerfass ◽

Ricardo Freitas

Keyword(s):

Volcanic Rocks ◽

Alkali Feldspar ◽

Southern Brazil ◽

Santa Barbara ◽

Crystallization Sequence ◽

Mafic Rocks ◽

Mineralogical Study ◽

Felsic Volcanic ◽

Felsic Volcanic Rocks ◽

Felsic Rocks

A mineralogical study was carried out in mafic and felsic volcanic rocks of the Acampamento Velho Alloformation at Cerro do Bugio, Perau and Serra de Santa Bárbara areas (Camaquã Basin) in southern Brazil. The Acampamento Velho bimodal event consists of two associations: lower mafic at the base and upper felsic at the top. Plagioclase and alkali-feldspar were studied using an electronic microprobe, and magnetite, ilmenite, rutile, illite and alkali-feldspar were investigated through scanning electron microscopy. The rocks were affected by a process of late sodic autometasomatism. In mafic rocks, Ca-plagioclase was transformed to albite and pyroxenes were altered. In felsic rocks, sanidine was partially pseudomorphosed, generating heterogeneous alkali-feldspar. In this association, unstable Ti-rich magnetite was replaced by rutile and ilmenite. In mafic rocks, the crystallization sequence was: (1) Ti-rich magnetite (?), (2) pyroxene and Ca-plagioclase, (3) albite (alteration to Ca-plagioclase), (4) sericite, chlorite and calcite (alteration to pyroxene), and kaolinite (alteration to plagioclase/albite). In felsic rocks: (1) zircon, (2) Ti-rich magnetite, (3) sanidine, (4) quartz. The introduction of late Na-rich fluids, generated the formation of (5) heterogeneous alkali-feldspar, (6) ilmenite and rutile from the Ti-rich magnetite, (7) albite in the spherulites. Finally, alteration of sanidine, vitroclasts and pumice to (8) illite.

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