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Showing 1 to 13 of 13 for “"Allanite"”.
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Unlocking the Rare Earth Elements Potential of Allanite: A Comprehensive Study of Beneficiation and Leaching
Allanite is a widely distributed accessory rare-earth silicate mineral, commonly associated with garnet, biotite, and feldspar in igneous and metamorphic rocks, and occasionally found in hydrothermal veins. Containing between 14–33 wt.% total rare earth elements (TREEs), allanite is dominated by …
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Synthesis and crystal chemistry of lanthanide allanites
… the crystal chemical characterization of natural allanites. To overcome these problems, allanites, Ca(REE)Fe²+Al₂Si₃O₁₂(OH), where REE = La, La-Ce, Ce, Nd, Sm, Eu, Gd, Er, Dy, Yb and Y have been synthesized hydrothermally from unbuffered and buffered oxide mixes at 500 to 650°C, 5.5 kbar (550 …
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Geology & Geochemistry of the Kingman Feldspar, Rare Metals and Wagon Bow Pegmatites
… which, in some cases, is sufficiently high that allanite is Nd dominant, thus a new mineral species, allanite-Nd.
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The controls of radioelement distribution in the Etive and Cairngorm granites: Implications for heat production
… crystallisation of apatite + zircon + sphene ± allanite and chevkinite. Later, thorite and monazite became important thorium-hosts. Locally, enhanced uranium levels in the Starav Granites followed expulsion and limited outward migration of uranium-rich residual fluids. The distribution of …
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The Fraser Lakes Zone B U-Th-REE deposit and its host rocks : implications for pegmatite- and leucogranite-hosted U-Th-REE deposits in northern Saskatchewan, Canada
… uranoan thorite, zircon, and rare coffinite and allanite, and are typically U- ±Th-enriched (Th/U ~1). The Group B pegmatites, in the central part of the fold nose, are Th- and LREE- enriched (Th/U up to ~20) and contain small amounts of monazite, uranoan thorite, and zircon, with rare allanite …
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Petrogenesis of the Springfield Granodiorite, southeast Pennsylvania Piedmont
… quartz, microcline, biotite, epidote (often with allanite cores) and trace amounts of hornblende. Accessory minerals include sphene, magnetite, apatite and zircon. The magmatic assemblage of quartz+two feldspars+biotite+sphene+hornblende+magnetite permits its utilization of AI-in-hornblende as a …
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Petrogenesis of a migmatite, Penobscot County, Maine: ultrametamorphism or intrusion?
… hornblendebearing inclusions, primary titanite, allanite, hornblende, and apatite included in biotite or hornblende), or S-type (tourmaline and red-brown biotite). They are conformable with melanosome (Bucksport) layering, and vary in outcrop from 7-88% areally, and in composition from tonalite …
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ΠΕΤΡΟΛΟΓΙΑ ΚΑΙ ΓΕΩΧΗΜΕΙΑ ΤΟΥ ΠΛΟΥΤΩΝΙΤΗ ΤΗΣ ΕΛΑΤΙΑΣ (ΚΕΝΤΡΙΚΗ ΡΟΔΟΠΗ)
… AND MUSCORITE APPEAR AT SUBORDINATE PROPORTIONS. ALLANITE EPIDOTE, SPHENE, APATITE, ZIRCON, CHLORITE AND OPAQUE MINERALS APPEAR AT ACCESSORY QUANTITIES. FORTHE GEOCHEMICAL STUDY OF THE ELATIA PLUTONIC ROCKS MAJOR (SI,TI,AL,FE,MG,CA, AND TRACE (RB,SR,BA,ZR,V,CR,SC,NB,NI,ZN,PB,U,TH,V,LA,CE,ND) …
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Petrografia, litoquímica, química mineral e termobarometria de rochas cálcioalcalinas de alto K de textura porfirítica, ediacaranas, no extremo NE da Província Borborema (NE do Brasil)
… mafic minerals; and titanite, opaque minerals, allanite, epidote, apatite and zircon are the accessories minerals. The Monte das Gameleiras granite shows metaluminous aluminium saturation index, whereas the others plutons metaluminous to peraluminous. In geochemical diagrams, the granites …
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Geological and geochemical aspects of the Loch Loyal Alkaline Complex, Sutherland
… is due chiefly to the thorium content of allanite. Within the pegmatites of Sgor Chaonasaid at the northern extremity of the Loyal range a zonation between galena and silicate minerals exists in which silver and copper form complex sulphides such as stromoyerite. The origin of the Loyal …
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From the Appalachians to the Alps: Constraints on the Timing, Duration, and Conditions of Metamorphism at Convergent Margins
… during the Alleghanian. In chapter 3, monazite, allanite, and zircon laser ablation split-stream petrochronology are used to constrain the timing of poly-metamorphism and develop a tectonic model for the SRA. The SRA preserves evidence for at least three orogenic events, each with a relatively …
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Uranium-series isotope constraints on magma generation and differentiation in the central Oregon Cascades
… partial melt, generated in the presence of an allanite/monazite-free residue as a consequence of the hot conditions within the subducting slab. This implies melt addition to the sub-arc mantle << 150 k.y. prior to melting. The majority of the mafic lavas erupted in the study area have been …
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Association of S-type and I-type granitoids in the Neoproterozoic Cameroon orogenic belt, Bafoussam area, West Cameroon : geology, geochemistry and petrogenesis
… such as apatite,zircon, monazite, titanite, allanite, ilmenite and magnetite. Sericite, epidote and chlorite are secondary minerals. In addition, the two-mica granitoid contains primary muscovite and sometimes igneous garnet. In the granitoids, potassium feldspar is orthoclase (microcline and …