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Article
Open AccessEarly-paleozoic rapakivi-textured granite from the North Qinling (Central China): implications for crust–mantle interactions in a post-collisional setting
Rapakivi granite is characterized by its unique structure, which has important implications for tectonic settings, magmatic processes, and crust–mantle interactions. In this study, we conducted a combined anal...
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Article
Open AccessDeciphering magmatic processes from plagioclase, clinopyroxene and amphibole chemistry and textures: A case study of a basaltic lava flow in the Basque-Cantabrian Basin (Northern Spain)
This paper addresses the study of a pillow lava interbedded with Late Albian-Early Cenomanian sediments that crops out in Armintza (Bizkaia, Northern Spain). The lava flow is an alkaline basalt with abundant m...
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Article
Open AccessHigh-grade metamorphism of banded iron formations: the role of saline fluids in promoting the growth of pyroxene and garnet reaction textures along magnetite-quartz grain boundaries
Metamorphosed banded iron formation (BIF) in granulite-amphibolite facies, tonalitic orthogneisses from a series of locations in the Kolli Massif of southern India are described and analysed with regard to the...
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Article
Open AccessNoble and base metal geochemistry of late- to post-orogenic mafic dykes from central Spain
The post-tectonic and post-orogenic mafic rocks from the Spanish Central System (SCS) (Iberian Massif) include dyke swarms of shoshonitic (microgabbros) and alkaline (lamprophyres and diabases) geochemical aff...
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Article
Open AccessGeochemistry and formation of agate-bearing lithophysae in Lower Permian volcanics of the NW-Saxonian Basin (Germany)
Geochemical and mineralogical investigations of the Lower Permian Kemmlitz rhyolite within the NW-Saxonian Basin (Germany) and associated lithophysae (high-temperature crystallization domains) as well as agate...
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Open AccessResponse to: Discussion on “Syn-metamorphic sulfidation of the Gamsberg zinc deposit, South Africa” by Stefan Höhn, Hartwig E. Frimmel, and Westley Price
Cawood et al. (this issue) critize our hypothesis of a pre-Klondikean weathering/oxidation event having affected the Aggeneys-Gamsberg ore district. Instead, they reinforce the long-held view that the sulfide ...
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Open AccessInterpretation of wide zircon U–Pb age distributions in durbachite-type Variscan granitoid in the Mórágy Hills
In situ U–Pb analyses were performed on SEM-BSE, SEM-CL and Raman mapped zircons from the Variscan granitoids exposed in the Mórágy pluton, Hungary. However, the routinely used LA-ICP-MS could result only in r...
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Article
Open AccessMallestigite, Pb3Sb(SO4)(AsO4)(OH)6·3H2O, from the type locality – new data, crystal structure, and structural relationships
A report of the supergene mineral mallestigite, Pb3Sb5+(SO4)(AsO4)(OH)6·3H2O, from the type locality Neufinkenstein-Grabanz district, Mallestiger Mittagskogel, Carinthia, Austria, is given in order to close gaps ...
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Article
Open AccessLa Queglia carbonatitic melnöite: a notable example of an ultra-alkaline rock variant in Italy
Very primitive ultramafic igneous rocks occur at Mt. La Queglia (Abruzzo, Italy). They form a strongly deformed sill–dyke system now tilted vertically. These rocks were initially classified as alnöite and, sub...
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Article
Open AccessCarbonatite-melilitite-phosphate immiscible melts from the aragonite stability field entrained from the mantle by a Pliocene basalt
A plagioclase megacryst containing composite crystal-glass inclusions was ejected in a Pliocene basaltic diatreme in the Carpathian back-arc basin (Pannonian Basin). The megacryst grew from phonolitic melt, re...
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Open AccessEarly Cretaceous ultramafic-alkaline-carbonatite magmatism in the Shillong Plateau-Mikir Hills, northeastern India – a synthesis
A comprehensive mineralogical, geochemical and isotopic review of six ultramafic-alkaline-carbonatite magmatic intrusions of the Shillong Plateau (Sung Valley, Jasra, Swangkre-Rongjeng, and Mawpyut) and Mikir ...
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Article
Open AccessOn the homeotypes of kobellite
Kobellite is a Pb-Bi-Sb sulfosalt with minor amounts of (Cu, Fe) and with the crystal structure composed of two types of rods, one of which has unusual lateral extensions (‘lobes’), which depart from the usual...
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Article
Open AccessThe use of geochemical methods to pinpoint the origin of ancient white marbles
“Multi-method-approach” has now been for many years the buzzword in marble provenance analysis. Nevertheless a true combination of the results of different analytical methods is rarely applied in the sense of ...
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Article
Open AccessAre the [6]-coordinated sites in tourmaline in certain cases partially vacant?
Tourmaline has two different [6]-coordinated sites, the Y site and the Z site. Vacancies were reported from both sites. Based on high-quality chemical and single-crystal structural data it usually needs increa...
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Article
Open AccessConcerning the incorporation of potassium in the crystal structure of combeite (Na2Ca2Si3O9)
Potassium incorporation in the structure of combeite has been studied in detail. Since natural combeites are known to contain only small amounts of potassium focus was laid on the Na-rich part of a hypothetica...
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Article
Open AccessA crystal structure refinement of uralolite, Ca2Be4(PO4)3(OH)3∙5H2O, from Weinebene, Austria
The crystal structure of uralolite, Ca2Be4(PO4)3(OH)3·5H2O, from the spodumene deposit of Weinebene, Carinthia, Austria, has been refined with X-ray single crystal data gathered on a CCD diffractometer. Uralolite...
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Article
Open AccessPrachařite, CaSb5+2(As3+2O5)2O2·10H2O, a new mineral from Lavrion, Greece
Prachařite, ideally CaSb5+2(As3+2O5)2O2·10H2O, is a new mineral found in underground workings of the Plaka Mine No. 80, Plaka, Lavrion Mining District, Attica, Greece. It occurs as colourless to white, thin tabul...
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Article
Open AccessStructural studies on synthetic A2−x[M2(TeO3)3]·nH2O phases (A = Na, K, Rb, Cs; M = Mn, Co, Ni, Cu, Zn) with zemannite-type structures
During a systematic study on formation conditions of new compounds with zemannite-type structures, crystals of ten new oxidotellurate(IV) phases were grown under hydrothermal conditions, partially by employing...
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Article
Open AccessKhurayyimite Ca7Zn4(Si2O7)2(OH)10·4H2O: a mineral with unusual loop-branched sechser single chains
The new mineral khurayyimite Ca7Zn4(Si2O7)2(OH)10·4H2O occurs in colorless spherulitic aggregates in small cavities of altered spurrite marbles located in the northern part of the Siwaqa pyrometamorphic rock area...
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Open AccessCrystal structure and optical absorption spectra of LiCo(SO4)OH and its remarkable relationship to the Zn-Mn-silicate hodgkinsonite
Crystals of the compound LiCo(SO4)OH were synthesised at low-hydrothermal conditions, and the crystal structure was determined and refined from single crystal X-ray diffraction data. LiCo(SO4)OH crystallises mono...
