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REE-bearing minerals in sediment-hosted stratiform pyrite mineralization zones of the Wiśniówka area (Holy Cross Mts., Poland)

Migaszewski Zdzisław M., Gałuszka Agnieszka, Zielińśki Grzegorz

Geological Quarterly

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2023

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Vol. 67, No. 2

art. no. 17

EN

There are two arsenical pyrite (As-FeS2mineralization zones cropping out in the Podwiśniówka and Wiśniówka Duża quarries where quartzites and quartzitic sandstones have been extracted for over a century. A large amount of pyrite in the Wiśniówka siliciclastics is unusual in the hard rock mining throughout the world. The pyritiferous beds contain a variety of REE-bearing minerals, including a crandallite series of aluminum-phosphate-sulfate (APS) minerals, e.g., predominant goyazite SrHAl3[(PO4)2(OH)6] with subordinate gorceixite BaHAl3[(PO4)2(OH)6] and very occasional crandallite CaHAl3[(PO4)2(OH)6]. By contrast, the other REE-phosphate minerals, e.g., xenotime YPO4, bur particularly monazite CePO4 occur in a lesser amount. Goyazite prevails somewhat in the Podwiśniówka beds whereas xenotime in the Wiśniówka Duża beds. Of the other REE-bearing minerals, bastnäsite REECO3(F,OH), florencite (REE)Al3(PO4)2(OH)6 and synchysite CaCe[CO3]2F occur in trace amounts. Interestingly, the quite common phosphate minerals, i.e., wavellite (Al.3[(OH,F)3|(PO4)2]×5H2O and variscite Al[PO4]×2H2O) are depleted in REEs with only Ce attaining 0.09 wt.% as documented by an electron-probe microanalysis. In contrast to quartzites/quartzitic sandstones, carbonaceous clayey-silty shales and bentonites/tuffites are distinctly enriched in REE-bearing minerals. This diversity is also mirrored in the mean total REE concentrations varying from 204 to 314 mg/kg, in clayey-silty shales and bentonites, attaining 457 mg/kg in some Podwiśniówka shale beds. Results of this and the previous petrographic, mineralogical and geochemical studies have indicated that REE-bearing minerals formed generally along with As-rich pyrite, nacrite/dickite and probably TiO2 polymorphs as a result of multiphase hydrothermal vent activity that took place in the Wiśniówka Late Cambrian sedimentary basin. This evidence is also backed up by the values of LREENASC/HREENASC (1.44–1.75) and Eu/EuNASC (1.24–1.30) coefficients in the clayey-silty shales. This positive Eu anomaly (31.20) points to the formation of REE-bearing minerals in a reducing environment.

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Charakterystyka morfologiczno-mineralogiczna konkrecji polimetalicznych ze strefy Clarion-Clipperton na Oceanie Spokojnym – wyniki wstępne

Kozłowska-Roman Agata, Mikulski Stanisław Z.

Przegląd Geologiczny

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2019

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Vol. 67, nr 3

169--172

EN

Manganese nodules, known also as polymetallic nodules, from the Clarion-Clipperton Zone on the Pacific Ocean were examined by the electron microprobe method to determine their chemical and mineralogical compositions. Two different types of layers were distinguished and total metal content was determined. Macroscopic investigations were also described.

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Digital Concentration-Distribution Models - tools for a describing heterogeneity of the hybridized magmatic mass as reflected in elemental concentration of growing crystal

Śmigielski M., Słaby E., Domonik A.

Acta Geologica Polonica

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2012

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Vol. 62, no. 1

129-141

EN

Raster digital models (digital concentration-distribution models - DC-DMs) as interpolations of geochemical data are proposed as a new tool to depict the crystal growth mechanism in a magmatic environment. The Natural Neighbour method is proposed for interpolation of Electron Microprobe Analysis (EMPA) data; the Natural Neighbour method and Kriging method are proposed for interpolating data collected by the LA-ICP-MS method. The crystal growth texture was analysed with the application of DC-DM derivatives: 3D surface models, shaded relief images, aspect and slope maps. The magmatic mass properties were depicted with the application of solid models. Correlation between the distributions of two elements on a single crystal transect was made by operations on the obtained raster DC-DMs. The methodology presented is a universal one but it seems to be significant for the depiction of magma mixing processes and the heterogeneity of the magmatic mass.