Compilation of xenotime data sources used for this study. Although the occurrence of xenotime is relatively common and widespread in many common rocks, …

Xenotime is an ideal mineral for U-Th-Pb isotopic dating because of its relatively high U and Th contents, but typically low concentration of common Pb. These characteristics, and the fact that it is widespread throughout various types of rocks, suggest that the U-Th-Pb dating of xenotime has broad applications. Studies of U-Pb dating on …

The textural relations and chemical composition of xenotime indicate that the large xenotime grains crystallized from melt almost simultaneously with zircon, monazite and tourmaline. ... Harlov DE, Wirth R, Förster H-J (2005) An experimental study of dissolution-reprecipitation in fluorapatite: fluid infiltration and the formation of …

The vast majority of rare earth element (REE) deposits are known to form at high temperatures in association with carbonatitic and peralkaline magmatism (e.g., Migdisov et al., 2016).However, lesser-known hydrothermal deposits of heavy REE (HREE)–enriched xenotime (YPO 4) also occur within sedimentary basins (e.g., Rabiei …

The existence of monazite and xenotime inclusions in apatite is a relatively common phenomena in both metamorphic (Harlov and Förster 2002; Hansen and Harlov 2007; Harlov et al. 2007) as well as igneous (Harlov et al. 2002a, b; Ziemann et al. 2005) rocks.Experimentally it has been demonstrated for both fluorapatite as well as …

Xenotime overgrowths on detrital zircon in siliciclastic sediments have been reported in numerous studies. However, in natural samples, solid solution of zircon and xenotime is limited to near-end-member compositions. In order to characterize the interface region between both minerals and to draw inferences on the growth mechanisms of …

Xenotime grows in sediments during diagenesis, in low- to granulite-grade metamorphic rocks, in migmatites, and is common in peraluminous igneous rocks. …

(c) compositionally heterogenous thorite–xenotime–zircon solid solution. The bright rim around the grain marks the damage zone in the enclosing mica caused by the radioactive decay of the ...

Zircon, monazite, and xenotime have proven to be valuable chronometers for various geological processes due to their commonly high-U–Th and low common Pb contents. However, zircons that have crystallized in highly fractionated granites often have such high-U contents that radiation damage can lead to scattered U–Pb ages when …

Fresh black shale from a quarry closed to a drill core (118°06′0.7′′E; 29°55′25.7′′N, Fig. 1 b) from Guan et al. (2014) was selected for this study, since the stratigraphic horizon of this sample can be correlated to the fossil-rich zone in the lower part of Member II reported by Yuan et al. (2011).The SEM observations demonstrate that our …

General Xenotime-(Y) Information : Chemical Formula: YPO4 : Composition: Molecular Weight = 183.88 gm Yttrium 48.35 % Y 61.40 % Y 2 O 3 Phosphorus 16.84 % P 38.60 % P 2 O 5 Oxygen 34.80 % O _____ _____ 100.00 % 100.00 % = TOTAL OXIDE: Empirical Formula: Y(PO 4) Environment: Minor accessory mineral in both acidic and alkalic …

Xenotime. Xenotime is first milled to a required particle size and then roasted in a furnace. Then, it undergoes a digestion with concentrated sulfuric acid (93%) in an acid to a solid weight ratio of 2.6:1 at 250–300°C for 1–2 h.28 Leaching is uneconomical for concentrates containing less than 10% xenotime. The rare earth phosphates are ...

Chemical Formula: YPO4. Composition: Molecular Weight = 183.88 gm. Yttrium 48.35 % Y 61.40 % Y 2 O 3. Phosphorus 16.84 % P 38.60 % P 2 O 5. Oxygen 34.80 % O. ______ …

In this study a Th-bearing monazite from a Brazil beach sand, a low Th monazite from a Malawi carbonatite, and a xenotime from a pegmatite in northern Pakistan were experimentally metasomatised in a series of common metamorphic and igneous fluids at 600°C/500 MPa and 900°C/1000 MPa.

Xenotime-(Y) YPO4 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Tetragonal. Point Group: 4/m2/m2/m. ... C.M. Gramaccioli (1991) The chemical composition of xenotime from fissures and pegmatites in the Alps. Can. Mineral., 29, 69–75. (4) Y. Ni, J.M. Hughes, and A.N. Mariano (1995) Crystal

This study investigates the paragenesis and ore mineral composition of xenotime [(Y,HREE)PO4] and florencite [LREEAl3(PO4)2(OH)6] from heavy rare earth element (HREE) deposits/prospects of the ...

Xenotime-(Y) and monazite are common accessory phosphates that control the rare earth element (REE) budget in many rocks. Whereas monazite preferentially incorporates the light REE (LREE) from La to Gd, the xenotime incorporates the heavy REE (HREE) from Tb to Lu (Ni et al. 1995).For monazite, the REE patterns are steep …

As xenotime is found in placer deposits, it is easy to process, and the concentrate carries 40–60% Y 2 O 3 with a mixture of other rare earth oxides. The processing route of xenotime is similar to that of monazite. 2.5.2 Ion Adsorption Clays. Commercial mining and processing of these types of ores are currently exercised only in …

By comparing the composition of XN01–XN05 (Table 3) against other xenotimes, we observed a higher correlation between the Datas xenotime and hydrothermal xenotime studied by Lan et al. and …

Monazite [(Ce, La)PO 4 ] and xenotime [YPO 4 ] are often found together in many deposits, wherein, monazite occurs as a major mineral and xenotime presents as a minor mineral (Chelgani et al. 2015 ...

The crystal chemistry and crystal structure of the rare earth element phosphates, monazite-(Ce), Ce(PO 4), and xenotime-(Y), Y(PO 4), as well as the arsenates, gasparite-(Ce), Ce(AsO 4), and chernovite-(Y), Y(AsO 4), from the hydrothermal quartz-bearing fissures, related to pegmatites overprinted by amphibolite facies, …

PDF | On Sep 1, 1995, H.-J. Förster and others published Composition of monazite and xenotime from the Fichtelgebirge granites - An electron microprobe study | Find, read and cite all the ...

3. Microanalysis of xenotime for geochemistry and geochronology 3.1. Introduction Measuring the composition of REE orthophosphate minerals (monazite and xenotime) …

3.2.1.3 Xenotime. Xenotime (YPO 4) is less commonly observed than monazite but, according to Hetherington et al. this may be explained by the smaller grain size of this mineral, meaning that it is less likely to be identified. In addition to this, xenotime has a bulk rock composition that is not so stable, resulting in possible …

Xenotime is very selective towards HREE and Y. EPMA and LA–ICP–MS analysis revealed that HREE (notably Dy, Er, Gd and Yb) and Y occur predominantly within xenotime and that the xenotime composition is consistent across all prospects and xenotime generations with the exception of some grain margins, which are particularly …

xenotime, widely distributed phosphate mineral, yttrium phosphate (YPO 4 ), though large proportions of erbium commonly replace yttrium), that occurs as brown, glassy crystals, crystal aggregates, or rosettes in igneous rocks and associated pegmatites, in quartzose and micaceous gneiss, and commonly in detrital material.

The main characteristics of xenotime are listed below: (1) The content of yttrium is high while that of the light rare earths is low (Table 12). (2) The content of thorium is lower …

Over 200 REE-bearing minerals occur in a variety of mineral classes, including phosphates, fluorcarbonates, oxides, silicates, and fluorides (Table 2) [3, 4, 8].Monazite ((Ce,La,Nd,Th)PO 4), xenotime ((HREE,Y)PO 4), and bastnaesite ((Ce,La)(CO 3)F) are the common natural economic REE-minerals mined worldwide [2, 3, …