scholarly journals Garnets from Val d’Ala Rodingites, Piedmont, Italy: An Investigation of Their Gemological, Spectroscopic and Crystal Chemical Properties

Minerals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 728 ◽  
Author(s):  
Valeria Diella ◽  
Rosangela Bocchio ◽  
Nicoletta Marinoni ◽  
Franca Caucia ◽  
Maria Iole Spalla ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Inductively Coupled Plasma ◽  
Chemical Properties ◽  
Western Alps ◽  
Drift Spectroscopy ◽  
X Ray ◽  
Heavy Rare Earth Elements ◽  
Diffuse Reflectance Infrared

In Val d’Ala (Piedmont, Western Alps, Italy), the more interesting rocks for the mineralogical research are represented by rodingites (rich in mineralized veins and fractures) associated with serpentinites in the eclogitized oceanic crust of Piemonte Zone, south of Gran Paradiso Massif. Among the vein-filling minerals, garnets are the most appreciated as mineral specimens and, in less degree despite their vivid and rich colors, for their potential as gem-quality materials. This study provides a complete gemological characterization of five faceted samples and offers new information by means of Synchrotron X-ray computed micro-tomography imaging gem features. Electron-probe microanalysis (EMPA) and laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) established that the chemical composition of garnets from different localities, resulted both close to pure andradite, enriched in light rare earth elements (LREE) with a positive Eu anomaly, and grossular-andradite solid solution (grandite), enriched in heavy rare earth elements (HREE). X-ray powder diffraction analyses indicate the possible coexistence of almost pure grossular and andradite. A spectroscopic approach, commonly used with gem-like material, by Raman and diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, completes the characterization of the samples. The new data on the textural and geochemical features of the grandite and andradite garnets suggest local growth processes under various chemical and oxidation conditions of metasomatic and metamorphic fluids interacting with the host-rocks. Garnets represent long-lasting mineral records of the complex geological history of the Val d’Ala rodingitic dikes during their oceanic- and subduction-related metamorphic evolution.

Affinity of dual energy X-ray transmission sensors on minerals bearing heavy rare earth elements

2020 ◽  
Vol 147 ◽  
pp. 106151 ◽  
Author(s):  
Moacir Medeiros Veras ◽  
Aaron Samuel Young ◽  
Cristiano Rocha Born ◽  
Artur Szewczuk ◽  
Artur Cezar Bastos Neto ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Dual Energy ◽  
Heavy Rare Earth ◽  
X Ray ◽  
Heavy Rare Earth Elements

Quantitative Cathodoluminescence Mapping with Application to a Kalgoorlie Scheelite

2009 ◽  
Vol 15 (3) ◽  
pp. 222-230 ◽  
Author(s):  
Colin M. MacRae ◽  
Nicholas C. Wilson ◽  
Joel Brugger
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Trace Element ◽  
Inductively Coupled Plasma ◽  
Trace Element Level ◽  
Gaussian Peak ◽  
X Ray ◽  
Element Abundances ◽  
Inductively Coupled ◽  
Peak Fitting

AbstractA method for the analysis of cathodoluminescence spectra is described that enables quantitative trace-element-level distributions to be mapped within minerals and materials. Cathodoluminescence intensities for a number of rare earth elements are determined by Gaussian peak fitting, and these intensities show positive correlation with independently measured concentrations down to parts per million levels. The ability to quantify cathodoluminescence spectra provides a powerful tool to determine both trace element abundances and charge state, while major elemental levels can be determined using more traditional X-ray spectrometry. To illustrate the approach, a scheelite from Kalgoorlie, Western Australia, is hyperspectrally mapped and the cathodoluminescence is calibrated against microanalyses collected using a laser ablation inductively coupled plasma mass spectrometer. Trace element maps show micron scale zoning for the rare earth elements Sm3+, Dy3+, Er3+, and Eu3+/Eu2+. The distribution of Eu2+/Eu3+ suggests that both valences of Eu have been preserved in the scheelite since its crystallization 1.63 billion years ago.

scholarly journals Rock alteration at the post-Variscan nonconformity: implications for Carboniferous–Permian surface weathering versus burial diagenesis and paleoclimate evaluation

Solid Earth ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 1165-1184
Author(s):  
Fei Liang ◽  
Jun Niu ◽  
Adrian Linsel ◽  
Matthias Hinderer ◽  
Dirk Scheuvens ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Basaltic Andesite ◽  
Inductively Coupled Plasma ◽  
Volcanic Rocks ◽  
Polarization Microscopy ◽  
Burial Diagenesis ◽  
X Ray ◽  
Physical Weathering ◽  
Geochemical Indices

Abstract. A nonconformity refers to a hiatal surface located between metamorphic or igneous rocks and overlying sedimentary or volcanic rocks. These surfaces are key features with respect to understanding the relations among climate, lithosphere and tectonic movements during ancient times. In this study, the petrological, mineralogical and geochemical characteristics of Variscan basement rock as well as its overlying Permian volcano-sedimentary succession from a drill core in the Sprendlinger Horst, Germany, are analyzed by means of polarization microscopy, and environmental scanning electron microscope, X-Ray diffraction, X-ray fluorescence and inductively coupled plasma mass spectrometry analyses. In the gabbroic diorite of the basement, the intensity of micro- and macro-fractures increases towards the top, indicating an intense physical weathering. The overlying Permian volcanic rock is a basaltic andesite that shows less intense physical weathering compared with the gabbroic diorite. In both segments, secondary minerals are dominated by illite and a mixed-layer phase of illite and smectite (I–S). The corrected chemical index of alteration (CIA) and the plagioclase index of alteration (PIA) indicate an intermediate to unweathered degree in the gabbroic diorite and an extreme to unweathered degree in the basaltic andesite. The τ values for both basaltic andesite and gabbroic diorite indicate an abnormal enrichment of K, Rb and Cs that cannot be observed in the overlying Permian sedimentary rocks. Accompanying minerals such as adularia suggest subsequent overprint by (K-rich) fluids during burial diagenesis which promoted the conversion from smectite to illite. The overall order of element depletion in both basaltic andesite and gabbroic diorite during the weathering process is as follows: large-ion lithophile elements (LILEs) > rare earth elements (REEs) > high-field-strength elements (HFSEs). Concerning the REEs, heavy rare earth elements (HREEs) are less depleted than light rare earth elements (LREEs). Our study shows that features of supergene physical and chemical paleo-weathering are well conserved at the post-Variscan nonconformity despite hypogene alteration. Both can be distinguished by characteristic minerals and geochemical indices. Based on these results, a new workflow to eliminate distractions for paleoclimate evaluation and evolution is developed.

scholarly journals Identification of rare-earth minerals associated to K-feldspar: Capacsaya project in Peru

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
J. Ochoa ◽  
E. Monteblanco ◽  
L. Cerpa ◽  
A. Gutarra-Espinoza ◽  
L. Avilés-Félix
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Size Range ◽  
X Ray Diffraction ◽  
High Concentration ◽  
Particle Size Range ◽  
X Ray ◽  
Rare Earth Minerals ◽  
Heavy Rare Earth Elements ◽  
The Rare Earth

AbstractA recently discovered the rare-earth-rich site in Capacsaya, located at 123 km northwest of Cusco, at the south of Peru, contains significant quantities of light and heavy rare-earth elements such as neodymium, lanthanum, cerium, europium, and yttrium. This work reports the identification of rare-earth elements and their associated minerals using scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction analyses. Five (5) samples extracted from different locations at the Capacsaya site were characterized and identified K-feldspar as the mineral associated with the rare-earth elements in a representative sample with a high concentration of lanthanum and cerium. The results showed rare-earth elements contained within the mineral phase monazite, being cerium the dominant element in the phase (La, Ce, Nd)PO$$_4$$ 4 . Finally, through the electrostatic separation process we demonstrate that it was possible to achieve an efficient separation of the K-feldspar phase in the particle size range 75–150 $$\upmu$$ μ m.

scholarly journals Lithological distribution of rare earth elements in automorphic and alluvial soils in the Bregalnica river basin

2015 ◽  
Vol 34 (1) ◽  
pp. 201 ◽  
Author(s):  
Biljana Balabanova ◽  
Trajce Stafilov ◽  
Robert Šajn
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
River Basin ◽  
Inductively Coupled Plasma ◽  
Anthropogenic Activities ◽  
Alluvial Soil ◽  
Inductively Coupled ◽  
Heavy Rare Earth Elements ◽  
Light Rare Earth Elements

<p>The present study gives an overview of the rare earth elements<strong> (</strong>REEs) distribution in automorphic and alluvial soil (top and sub soil sample) in the Bregalnica river environ. The elements contents were determined using inductively coupled plasma with mass spectrometry. The total sum of the light rare earth elements (ΣLREEs) in the whole investigated area ranges from 8.6-225 mg kg<sup>-1</sup>, while the total sum of the heavy rare earth elements (ΣHREEs) ranges from 0.92-33.7 mg kg<sup>-1</sup>. The distribution of the LREEs (La-Ce-Pr-Nd-Sm-Gd) is predominantly related to the Quaternary terraces and the Paleogene flysch. The anthropogenic activities that occur in the Pb-Zn surroundings and the Cu mineralization in the investigated area significantly influence the lithological distribution of this geochemical association of elements. On the other hand, the long-term deposition of the HREEs (Eu-Tb-Dy-Ho-Er-Tm-Yb-Lu) presents a typical geochemical marker of the area of the Bregalnica river basin.</p>

scholarly journals Characterization of Rare Earth Elements in Tailing of Ex-Tin Mining Sands from Singkep Island, Indonesia

2018 ◽  
Vol 7 (2) ◽  
pp. 131-137 ◽  
Author(s):  
Yanuar Hamzah ◽  
Muhammad Mardhiansyah ◽  
Liong Nyuk Firdaus
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rapid Determination ◽  
Mining Area ◽  
Economic Potential ◽  
Energy Dispersive Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

The objective of this research is to determine the rare earth elements (REEs) from themonazite minerals content of several tin tailing sands (TTS)of ex-tin mining area in Kuala Raya Singkep Island, Indonesia. We used the energy dispersive analysis of  X-ray (EDAX)-scanning electron microscopy (SEM) and x-ray diffraction (XRD) to characterize the contents of the samples. The coupled analytical of XRD with SEM/EDX approach enabled to be used for mineralogical identification on the heavy mineral as a rapid determination approach. The analysis of the samples indicates only the presence of REEs including lanthanum (La), cerium (Ce), and thorium (Th) are consistent with the identification of monazite and minerals in the tailing sand. The results show that the average REEs consist of La at 0.2 .%, Ce at 7.8 %, and Th at 2.0% respectively. It is concluded that monazite minerals in TTS has an economic potential to be developed. These monazite minerals can be used as material for semiconductor devices.   

scholarly journals KARAKTERISTIK DAN GENESA PENGAYAAN UNSUR-UNSUR TANAH JARANG PADA BATUBARA LAPANGAN BATUBARA MUARA TIGA BESAR UTARA, TANJUNG ENIM, CEKUNGAN SUMATERA SELATAN

2019 ◽  
Vol 14 (3) ◽  
pp. 198-212
Author(s):  
Ferian Anggara ◽  
Mutiara Cikasimi ◽  
Basuki Rahmat ◽  
Sigit Arso Wibisono ◽  
Rita Susilawati
Keyword(s):  
Rare Earth ◽  
Inductively Coupled Plasma ◽  
Emission Spectroscopy ◽  
Atomic Emission ◽  
X Ray Diffraction ◽  
Heavy Rare Earth ◽  
X Ray ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Heavy Rare Earth Elements

Batubara telah menjadi salah satu sumber alternatif unsur-unsur tanah jarang (UTJ) seiring dengan meningkatnya permintaan terhadap kebutuhan unsur-unsur tersebut. Kondisi geologis spesifik menyebabkan pengayaan konsentrasi UTJ pada batubara. Keterdapatan lapisan tipis material vulkanik (tonstein) pada Lapangan Batubara Muara Tiga Besar Utara, Formasi Muara Enim, Cekungan Sumatera Selatan menjadi salah satu indikasi terdapatnya pengayaan UTJ. Penelitian dilakukan menggunakan metode petrografi sayatan poles, analisis-analisis X-Ray Diffraction (XRD), proksimat, dan geokimia; Inductively Coupled Plasma-Mass/Atomic Emission Spectroscopy (ICP-MS/AES). Analisis geokimia menunjukkan pola distribusi UTJ didominasi oleh tipe UTJ Berat (Heavy Rare Earth Elements, HREE). Plot diagram nilai Coutl dan REOash menunjukkan prospek pengayaan UTJ termasuk ke dalam daerah prospek. Pola distribusi UTJ dan anomali redox sensitive dan redox non-sensitive menunjukkan tipe genetik pengayaan UTJ adalah tufaan. Pengayaan UTJ terjadi oleh proses pencucian alkaline tonstein yang terendapkan pada fase penggambutan dalam pembentukan batubara.

scholarly journals Composition of Garnet from the Xianghualing Skarn Sn Deposit, South China: Its Petrogenetic Significance and Exploration Potential

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 456 ◽  
Author(s):  
Fan Yu ◽  
Qihai Shu ◽  
Xudong Niu ◽  
Kai Xing ◽  
Linlong Li ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Inductively Coupled Plasma ◽  
Major And Trace Elements ◽  
Inductively Coupled ◽  
Metallogenic Belt ◽  
Icp Ms ◽  
Heavy Rare Earth Elements ◽  
Plasma Mass Spectrometry ◽  
Southern Hunan

The Xianghualing skarn Sn deposit in the southwestern part of the southern Hunan Metallogenic Belt is a large Sn deposit in the Nanling area. In this paper, the garnet has been analyzed by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to obtain the concentrations of the major and trace elements. The results reveal that the garnets from the Xianghualing deposit mainly belong to andradite-grossular (grandite) solid solution and are typically richer in Al than in Fe. They show enrichment in heavy rare earth elements (HREEs) and notably lower light rare earth elements (LREEs), and commonly negative Eu anomalies, indicative of a relatively reduced formation environment. The garnets have high Sn concentrations between 2313 ppm and 5766 ppm. It is also evident that there is a positive correlation between Sn and Fe, suggesting that Sn4+ substitutes into the garnets through substituting for Fe3+ in the octahedral position. Combined with previous studies, it can be recognized that the Sn concentrations of garnet in skarn Sn deposits are generally high, whereas the W concentrations are relatively low. This is just the opposite in garnets from skarn W deposits that typically have high W, but low Sn concentrations. In polymetallic skarn deposits with both economic Sn and W, the concentrations of both metals in garnets are relatively high, although varying greatly. Therefore, the Sn and W concentrations in garnets can be used to evaluate a skarn deposit’s potential to produce Sn and (or) W mineralization, which is helpful in exploration.

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