Gadolinite-(Nd), a new member of the gadolinite supergroup from Fe-REE deposits of Bastnas-type, Sweden

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F18%3A00101804" target="_blank" >RIV/00216224:14310/18:00101804 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68378271:_____/18:00498662

Výsledek na webu

<a href="http://dx.doi.org/10.1180/minmag.2017.081.047" target="_blank" >http://dx.doi.org/10.1180/minmag.2017.081.047</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1180/minmag.2017.081.047" target="_blank" >10.1180/minmag.2017.081.047</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Gadolinite-(Nd), a new member of the gadolinite supergroup from Fe-REE deposits of Bastnas-type, Sweden

Popis výsledku v původním jazyce

A new member of the gadolinite supergroup, gadolinite-(Nd), IMA2016-013, ideally Nd2FeBe2Si2O10, was found in the Malmkarra mine, similar to 3.5km WSW of Norberg, south-central Sweden, where it occurs in association with fluorbritholite-(Ce), vastmanlandite-(Ce), dollaseite-(Ce), bastnasite-(Ce) and tremolite. Gadolinite-(Nd) forms anhedral grains up to 150 mu m in size, commonly occurring as aggregates of olive green colour. The crystals are transparent with vitreous to adamantine lustre. Gadolinite-(Nd) is brittle with conchoidal fracture, no cleavage or parting was observed. It has a white streak, the Mohs hardness is 6.5-7 and the calculated density is 4.86gcm(-3). Optically, the mineral is weakly pleochroic in shades of olive green, biaxial (-), n=1.78(1), n((calc.))=1.80, n=1.81(1) measured in white light, 2V((meas.))=62(3)degrees. Electron-microprobe and laser ablation inductively coupled plasma mass spectrometry analysis [in wt.%] provided SiO2 21.77, Y2O3 5.49, La2O3 2.78, Ce-2 O-3 14.04, Pr2O3 3.28, Nd2O3 19.27, Sm2O3 5.30, Eu2O3 0.24, Gd2O3 4.10, Tb2O3 0.36, Dy2O3 1.32, Ho2O3 0.18, Er2O3 0.38, MgO 0.51, CaO 0.14, MnO 0.10, FeO 10.62, B2O3 0.10, BeOcalc. 8.99, H2Ocalc. 0.55 and total 99.52 giving the following empirical formula (based on 2 Si): (Nd0.632Ce0.472Y0.268Sm0.168Gd0.125Pr0.110La0.094Dy0.039Ca0.014Er0.011Tb0.011Eu0.008Ho0.008)(Sigma 1.957)(Fe0.816Mg0.070Mn0.008)(Sigma 0.894)(Be1.984B0.016)(Sigma 2.000)Si2O9.660OH0.337. A weak Raman vibration band at similar to 3525cm(-1) confirms the presence of water in the structure. Gadolinite-(Nd) is monoclinic, P2(1)/c, with a=4.8216(3) angstrom, b=7.6985(4) angstrom, c=10.1362(6) angstrom, beta =90.234(4)degrees, V=376.24(6) angstrom(3) and Z=2. The strongest X-ray diffraction lines are [d(obs) in angstrom (hkl) I-rel]: 4.830 (100) 72, 3.603 (021) 37, 3.191(-112) 52, 3.097 (013) 35, 2.888 (121) 100, 2.607(113) 49, 2.412 (200) 24. Along with the Malmkarra mine, gadolinite-(Nd) was also recorded also at Johannagruvan and Nya Bastnas. The minerals of the gadolinite subgroup together with fluorbritholite-(Ce) incorporate the highest fraction of medium-to-heavy rare-earth elements among associated rare-earth element minerals in the Malmkarra mine and possibly in all Bastnas-type deposits.

Název v anglickém jazyce

Gadolinite-(Nd), a new member of the gadolinite supergroup from Fe-REE deposits of Bastnas-type, Sweden

Popis výsledku anglicky

A new member of the gadolinite supergroup, gadolinite-(Nd), IMA2016-013, ideally Nd2FeBe2Si2O10, was found in the Malmkarra mine, similar to 3.5km WSW of Norberg, south-central Sweden, where it occurs in association with fluorbritholite-(Ce), vastmanlandite-(Ce), dollaseite-(Ce), bastnasite-(Ce) and tremolite. Gadolinite-(Nd) forms anhedral grains up to 150 mu m in size, commonly occurring as aggregates of olive green colour. The crystals are transparent with vitreous to adamantine lustre. Gadolinite-(Nd) is brittle with conchoidal fracture, no cleavage or parting was observed. It has a white streak, the Mohs hardness is 6.5-7 and the calculated density is 4.86gcm(-3). Optically, the mineral is weakly pleochroic in shades of olive green, biaxial (-), n=1.78(1), n((calc.))=1.80, n=1.81(1) measured in white light, 2V((meas.))=62(3)degrees. Electron-microprobe and laser ablation inductively coupled plasma mass spectrometry analysis [in wt.%] provided SiO2 21.77, Y2O3 5.49, La2O3 2.78, Ce-2 O-3 14.04, Pr2O3 3.28, Nd2O3 19.27, Sm2O3 5.30, Eu2O3 0.24, Gd2O3 4.10, Tb2O3 0.36, Dy2O3 1.32, Ho2O3 0.18, Er2O3 0.38, MgO 0.51, CaO 0.14, MnO 0.10, FeO 10.62, B2O3 0.10, BeOcalc. 8.99, H2Ocalc. 0.55 and total 99.52 giving the following empirical formula (based on 2 Si): (Nd0.632Ce0.472Y0.268Sm0.168Gd0.125Pr0.110La0.094Dy0.039Ca0.014Er0.011Tb0.011Eu0.008Ho0.008)(Sigma 1.957)(Fe0.816Mg0.070Mn0.008)(Sigma 0.894)(Be1.984B0.016)(Sigma 2.000)Si2O9.660OH0.337. A weak Raman vibration band at similar to 3525cm(-1) confirms the presence of water in the structure. Gadolinite-(Nd) is monoclinic, P2(1)/c, with a=4.8216(3) angstrom, b=7.6985(4) angstrom, c=10.1362(6) angstrom, beta =90.234(4)degrees, V=376.24(6) angstrom(3) and Z=2. The strongest X-ray diffraction lines are [d(obs) in angstrom (hkl) I-rel]: 4.830 (100) 72, 3.603 (021) 37, 3.191(-112) 52, 3.097 (013) 35, 2.888 (121) 100, 2.607(113) 49, 2.412 (200) 24. Along with the Malmkarra mine, gadolinite-(Nd) was also recorded also at Johannagruvan and Nya Bastnas. The minerals of the gadolinite subgroup together with fluorbritholite-(Ce) incorporate the highest fraction of medium-to-heavy rare-earth elements among associated rare-earth element minerals in the Malmkarra mine and possibly in all Bastnas-type deposits.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10504 - Mineralogy

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

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

Rok uplatnění

2018

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

82

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

13

Strana od-do

133-145

Kód UT WoS článku

000435650000007

EID výsledku v databázi Scopus

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