scholarly journals Rare Earth Elements as an Indicator to Origins of Skarn Deposits: Examples of the Kamioka Zn-Pb and Yoshiwara-Sannotake Cu(-Fe) Deposits in Japan

1999 ◽  
Vol 49 (4) ◽  
pp. 183-198 ◽  
Author(s):  
Yasuhiro Kato
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Skarn Deposits

Factors controlling the crystal morphology and chemistry of garnet in skarn deposits: A case study from the Cuihongshan polymetallic deposit, Lesser Xing'an Range, NE China

2019 ◽  
Vol 104 (10) ◽  
pp. 1455-1468
Author(s):  
Xianghui Fei ◽  
Zhaochong Zhang ◽  
Zhiguo Cheng ◽  
M. Santosh
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Relative Proportion ◽  
External Factors ◽  
Oscillatory Zoning ◽  
Type I ◽  
Type Ii ◽  
Ne China ◽  
Skarn Deposits ◽  
Compositional Variations

Abstract The grossular-andradite solid solutions in garnet from skarn deposits in relation to hydrothermal processes and physicochemical conditions of ore formation remain controversial. Here we investigate garnet occurring in association with calcic and magnesian skarn rocks in the Cuihongshan polymetallic skarn deposit of NE China. The calcic skarn rocks contain three types of garnets. (1) Prograde type I Al-rich anisotropic garnets display polysynthetic twinning and a compositional range of Grs18–80Adr10–75. This type of garnet shows markedly low rare earth element (REE) contents (3.27–78.26 ppm) and is strongly depleted in light rare earth elements (LREE, 0.57–44.65 ppm) relative to heavy rare earth elements (HREE, 2.31–59.19 ppm). They also display a significantly negative Eu anomaly (Eu/Eu* of 0.03–0.90). (2) Fe-rich retrograde type II garnets are anisotropic with oscillatory zoning and own wide compositional variations (Grs1–47Adr30–95) with flat REE (13.73–377.08 ppm) patterns. (3) Fe-rich retrograde type III isotropic garnets display oscillatory zoning and morphological transition from planar dodecahedral {110} crystal faces to {211} crystal faces in the margin. Types III garnets exhibit relatively narrow compositional variations of Grs0.1–12Adr85–97 with LREE-enrichment (0.80–51.87 ppm), flat HREE patterns (0.15–2.46 ppm) and strong positive Eu anomalies (Eu/Eu* of 0.93–27.07 with almost all >1). The magnesian skarn rocks contain euhedral isotropic type IV Mn-rich garnet veins with a composition of Grs10–23Sps48–62Alm14–29. All calcic garnets contain considerable Sn and W contents. Type II garnet containing intermediate compositions of andradite and grossular shows the highest Sn contents (64.36–2778.92 ppm), albeit the lowest W range (1.11–468.44 ppm). Birefringence of garnet is probably caused by strain from lattice mismatch at a twinning boundary or ion substitution near intermediate compositions of grossular-andradite. The fine-scale, sharp, and straight garnet zones are probably caused by self-organization, but the compositional variations of zones from core to rim are probably caused by external factors. The zoning is likely driven by external factors such as composition of the hydrothermal fluid. REE concentrations are probably influenced by the relative proportion and temperature of the system. Moreover, the LREE-HREE fractionation of garnet can be attributed to relative compositions of grossular-andradite system. The W and Sn concentrations in garnet can be used as indicators for the exploration of W-Sn skarn deposits.

Flame spectra of the rare-earth elements*

1962 ◽  
Vol 18 (4) ◽  
pp. 1127-1153
Author(s):  
V FASSEL ◽  
R CURRY ◽  
R KNISELEY
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
The Rare Earth

ESTIMATION OF THE ABUNDANCE AND DISTRIBUTION OF RARE EARTH ELEMENTS IN SOIL AROUND KADUNA REFINING AND PETROCHEMICAL COMPANY USING NUCLEAR TECHNIQUE

2020 ◽  
Vol 4 (2) ◽  
pp. 599-604
Author(s):  
Michael A. Onoja ◽  
P. H. Bukar ◽  
C. U. Omeje ◽  
A. M. Adamu
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Nuclear Technique ◽  
Flood Plains ◽  
Economic Exploitation ◽  
Rare Elements ◽  
Petrochemical Company ◽  
The Moment ◽  
Abundance And Distribution ◽  
Natural Pattern

Instrumental neutron activation analysis (INAA) technique was used to investigate the abundance and distribution of rare earth elements (REE) in soil around Kaduna Refinery. The aim of the study is to assess the rare elements potential of Nigeria for economic exploitation. Five REEs (La, Dy, Eu, Yb, and Lu) were detected in varying concentrations ranging from a minimum of 0.6 µg/g (Lu) to a maximum of 249.0 µg/g (La). The elements existed with trends consistent with the natural pattern of REEs in soil, showing significant Eu and Dy anomalies which characterize upper plains and flood plains. The levels of REEs in soil in the study area were generally slightly above background levels, with minimal (La, Dy, and Eu), moderate (Yb), and significant (Lu) enrichments and trending: Lu ˃Yb ˃ Eu ˃ Dy ˃ La. The abundance of the REEs investigated cannot establish a potential of Nigeria for economic exploitation of the mineral, hence, rare earth project in the study area is not viable at the moment.

Sc, Y, La-Lu Rare Earth Elements

1986 ◽  
Author(s):  
Ingeborg Hinz ◽  
Peter Kuhn ◽  
Ursula Vetter ◽  
Eberhard Warkentin
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements

Sc, Y, La-Lu, Rare Earth Elements

1989 ◽  
Author(s):  
Hiltrud Hein ◽  
Claus Koeppel ◽  
Ursula Vetter ◽  
Eberhard Warkentin
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements
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