Monazite-(Gd), a new Gd-dominant mineral of the monazite group from the Zimná Voda REE–U–Au quartz vein, Prakovce, Western Carpathians, Slovakia

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F23%3A00133039" target="_blank" >RIV/00216224:14310/23:00133039 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1180/mgm.2023.37" target="_blank" >https://doi.org/10.1180/mgm.2023.37</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1180/mgm.2023.37" target="_blank" >10.1180/mgm.2023.37</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Monazite-(Gd), a new Gd-dominant mineral of the monazite group from the Zimná Voda REE–U–Au quartz vein, Prakovce, Western Carpathians, Slovakia

Popis výsledku v původním jazyce

Monazite-(Gd), ideally GdPO4, is a new mineral of the monazite group. It was discovered near Prakovce-Zimna Voda, similar to 23 km WNW of Kosice, Western Carpathians, Slovakia. It forms anhedral domains (&lt;= 100 mu m, mostly 10-50 mu m in size), in close association with monazite-(Sm), Gd-bearing xenotime-(Y), Gd-bearing hingganite-(Y), fluorapatite and uraninite. All these minerals are hosted in a REE-U-Au quartz-muscovite vein, hosted in phyllites in an exocontact to granites. The density calculated using the average empirical formula and unit-cell parameters is 5.55 g/cm(3). The average chemical composition measured by means of electron microprobe is as follows (wt.%): P2O5 29.68, As2O5 0.15, SiO2 0.07, ThO2 0.01, UO2 0.04, Y2O3 1.30, La2O3 3.19, Ce2O3 6.93, Pr2O3 1.12, Nd2O3 10.56, Sm2O3 17.36, Eu2O3 1.49, Gd2O3 22.84, Tb2O3 1.57, Dy2O3 2.27, CaO 0.21, total 99.67. The corresponding empirical formula calculated on the basis of 4 oxygen atoms is: (Gd0.30Sm0.24Nd0.15Ce0.10La0.05Dy0.03Y0.03Tb0.02Eu0.02Pr0.02Ca0.01)(0.98)P1.01O4. The ideal formula is GdPO4. The monazite-type structure has been confirmed by micro-Raman spectroscopy and selected-area electron diffraction. Monazite-(Gd) is monoclinic, space group P2(1)/n, a = 6.703(1) angstrom, b = 6.914(1) angstrom, c = 6.383(1) angstrom, beta = 103.8(1)degrees, V = 287.3(1) angstrom(3) and Z = 4. The middle REE enrichment of monazite-(Gd) is shared with the associated Gd-bearing xenotime-(Y) to 'xenotime-(Gd)' and Gd-bearing hingganite-(Y). This exotic REE signature and precipitation of Gd-bearing mineral assemblage is a product of selective complexing and enrichment in middle REE in low-temperature hydrothermal fluids by alteration of primary uraninite, brannerite and fluorapatite on a micro-scale. The new mineral is named as an analogue of monazite-(La), monazite-(Ce), monazite-(Nd) and monazite-(Sm) but with Gd dominant among the REE.

Název v anglickém jazyce

Monazite-(Gd), a new Gd-dominant mineral of the monazite group from the Zimná Voda REE–U–Au quartz vein, Prakovce, Western Carpathians, Slovakia

Popis výsledku anglicky

Monazite-(Gd), ideally GdPO4, is a new mineral of the monazite group. It was discovered near Prakovce-Zimna Voda, similar to 23 km WNW of Kosice, Western Carpathians, Slovakia. It forms anhedral domains (&lt;= 100 mu m, mostly 10-50 mu m in size), in close association with monazite-(Sm), Gd-bearing xenotime-(Y), Gd-bearing hingganite-(Y), fluorapatite and uraninite. All these minerals are hosted in a REE-U-Au quartz-muscovite vein, hosted in phyllites in an exocontact to granites. The density calculated using the average empirical formula and unit-cell parameters is 5.55 g/cm(3). The average chemical composition measured by means of electron microprobe is as follows (wt.%): P2O5 29.68, As2O5 0.15, SiO2 0.07, ThO2 0.01, UO2 0.04, Y2O3 1.30, La2O3 3.19, Ce2O3 6.93, Pr2O3 1.12, Nd2O3 10.56, Sm2O3 17.36, Eu2O3 1.49, Gd2O3 22.84, Tb2O3 1.57, Dy2O3 2.27, CaO 0.21, total 99.67. The corresponding empirical formula calculated on the basis of 4 oxygen atoms is: (Gd0.30Sm0.24Nd0.15Ce0.10La0.05Dy0.03Y0.03Tb0.02Eu0.02Pr0.02Ca0.01)(0.98)P1.01O4. The ideal formula is GdPO4. The monazite-type structure has been confirmed by micro-Raman spectroscopy and selected-area electron diffraction. Monazite-(Gd) is monoclinic, space group P2(1)/n, a = 6.703(1) angstrom, b = 6.914(1) angstrom, c = 6.383(1) angstrom, beta = 103.8(1)degrees, V = 287.3(1) angstrom(3) and Z = 4. The middle REE enrichment of monazite-(Gd) is shared with the associated Gd-bearing xenotime-(Y) to 'xenotime-(Gd)' and Gd-bearing hingganite-(Y). This exotic REE signature and precipitation of Gd-bearing mineral assemblage is a product of selective complexing and enrichment in middle REE in low-temperature hydrothermal fluids by alteration of primary uraninite, brannerite and fluorapatite on a micro-scale. The new mineral is named as an analogue of monazite-(La), monazite-(Ce), monazite-(Nd) and monazite-(Sm) but with Gd dominant among the REE.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10504 - Mineralogy

Projekt

<a href="/cs/project/EF16_026%2F0008459" target="_blank" >EF16_026/0008459: Dlouhodobý výzkum geochemických bariér pro ukládání jaderného odpadu</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Mineralogical Magazine

ISSN

0026-461X

e-ISSN

—

Svazek periodika

87

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

7

Strana od-do

568-574

Kód UT WoS článku

001036300100001

EID výsledku v databázi Scopus

2-s2.0-85160775679