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Monazite chemical composition: some implications for monazite geochronology
Contributions to Mineralogy and Petrology, 1999An investigation of the chemical composition of monazite from a number of localities has been carried out. Samples used include monazites from metamorphic rocks, granitic rocks and a hydrothermal ore deposit. The REE distribution pattern of monazite varies greatly in accordance with its geological environment.
X. K. Zhu, R. K. O'Nions
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Industrial & Engineering Chemistry, 1961
A laboratory scale chlorination of Egyptian monazite sand concentrate was carried out at 900 deg C in a horizontal tube furnace, and the variables affecting the condensation and purity of the thorium chloride produced were studied. In 30 minutes, 97.8% of the monazite content was attacked.
O. M. Hilal, F. A. El. Gohary
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A laboratory scale chlorination of Egyptian monazite sand concentrate was carried out at 900 deg C in a horizontal tube furnace, and the variables affecting the condensation and purity of the thorium chloride produced were studied. In 30 minutes, 97.8% of the monazite content was attacked.
O. M. Hilal, F. A. El. Gohary
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Chemical Geology, 2008
Abstract Diffusion of Th has been characterized in synthetic monazite under dry conditions. The synthetic monazites (either pure CePO4, NdPO4, or a mixed LREE phosphate containing Ce, Nd, and Sm) were grown via a Na2CO3–MoO3 flux method. The sources of diffusant for the experiments were either synthesized ThSiO4 or CaTh(PO4)2 powders mixed with CePO4.
D J Cherniak
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Abstract Diffusion of Th has been characterized in synthetic monazite under dry conditions. The synthetic monazites (either pure CePO4, NdPO4, or a mixed LREE phosphate containing Ce, Nd, and Sm) were grown via a Na2CO3–MoO3 flux method. The sources of diffusant for the experiments were either synthesized ThSiO4 or CaTh(PO4)2 powders mixed with CePO4.
D J Cherniak
exaly +2 more sources
Zircon and Monazite as Geochronometers
Mineralogical Journal, 2022The paper discusses the results of U-Pb isotope dating of monazites and zircons from granitoids formed under PT conditions of granulite and amphibolite facies and gneisses, and crystalline shales that are like xenoliths in these granitoids of the Ukrainian Shield.
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The legacy of monazite processing in Brazil
Radiation Protection Dosimetry, 2005The exploitation of natural resources containing naturally occurring radionuclides may lead to enhanced levels of radioactive isotope and enhanced potential for exposure to naturally occurring radionuclides in products, by-products, residues or wastes. Such resources include, for instance, monazite, the processing of which, in Brazil, generated a great
Dejanira, da Costa Lauria +1 more
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Geochimica et Cosmochimica Acta, 1997
Abstract We have measured the tracer diffusion rate of Pb in natural, annealed, gem-quality monazite from Alexander Co., NC, USA, and Riverside Co., CA, USA. Observations from the literature concerning low T annealing in monazite suggest the possibility that Pb diffusion at geologic conditions occurs, in effect, within a similarly annealed lattice ...
Harold A. Smith, Bruno J. Giletti
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Abstract We have measured the tracer diffusion rate of Pb in natural, annealed, gem-quality monazite from Alexander Co., NC, USA, and Riverside Co., CA, USA. Observations from the literature concerning low T annealing in monazite suggest the possibility that Pb diffusion at geologic conditions occurs, in effect, within a similarly annealed lattice ...
Harold A. Smith, Bruno J. Giletti
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Earth and Planetary Science Letters, 2004
Abstract We report measurements of oxygen diffusion in natural monazites under both dry, 1-atm conditions and hydrothermal conditions. For dry experiments, 18O-enriched CePO4 powder and monazite crystals were sealed in Ag–Pd capsules with a solid buffer (to buffer at NNO) and annealed in 1-atm furnaces.
D.J. Cherniak +3 more
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Abstract We report measurements of oxygen diffusion in natural monazites under both dry, 1-atm conditions and hydrothermal conditions. For dry experiments, 18O-enriched CePO4 powder and monazite crystals were sealed in Ag–Pd capsules with a solid buffer (to buffer at NNO) and annealed in 1-atm furnaces.
D.J. Cherniak +3 more
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Nature, 1948
X-RAY examination of monazite has been carried out by Hadding1, Gliszczynski2 and Parrish3, and the space group and crystal class uniquely determined. According to Goldschmidt4, the thorium which is usually present is ‘‘captured during crystallization of the phosphate from its parent magma because of its favourable ionic size.
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X-RAY examination of monazite has been carried out by Hadding1, Gliszczynski2 and Parrish3, and the space group and crystal class uniquely determined. According to Goldschmidt4, the thorium which is usually present is ‘‘captured during crystallization of the phosphate from its parent magma because of its favourable ionic size.
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Deformation twinning in monazite
Acta Materialia, 2003Abstract Polycrystalline monazite (LaPO4) was deformed at room temperature by a spherical indenter. Deformation twins were identified by TEM in 70 grains. Five twin planes were found: (1 0 0) was by far the most common; (0 0 1) and (1 2 0) were less common; ( 1 2 2 ) was rare, and kinks in (1 2 0) twins were identified as irrational ′(
R.S Hay, D.B Marshall
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Monazite-Xenotime-Garnet Equilibrium in Metapelites and a New Monazite-Garnet Thermometer
Journal of Petrology, 2001Prograde suites of pelitic rocks were examined with electron microprobe INTRODUCTION and laser ablation inductively coupled plasma mass spectrometry to Monazite [(Ce,La,Th)PO4] plays an important role in determine the systematics of element partitioning between coexisting studies of igneous and metamorphic petrogenesis.
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