Mineralization: Quartz breccia & xenotime . Miner. Phosphate deposits are important REE resources. Prismatic - Crystals Shaped like Slender Prisms (e.g. Fig. (2) The content of thorium is lower than that in monazite (Table 13). Serra Dourada granite is one of the most REE-enriched of this province and locally reaches REE contents of almost 2000 ppm (Polo and Diener, 2013). Open-fill and disseminated Xenotime with hematite dusting . The compositional and textural variations of these granites are related to different depths of granitic body crystallization and the magma source (Lenharo et al., 2003; Dardenne and Schobbenhaus, 2001). S - Stereo Pair on/off - Start-Stop Rotation The company will exploit primary REE-bearing minerals such as xenotime, monazite, fergusonite, and minor allanite and pyrochlore and secondary minerals including bastnaesite and REE-adsorption clays. Mouse 9 images. In thin section: high birefringence, high relief, and pale yellow color. 22 shows the powder X-ray diffraction (PXRD) patterns of three zircon samples from different localities that suggest various crystallinity of zircon: from high crystallinity to fully amorphous. Zagi Mountain, Hameed Abad Kafoor Dheri, Peshawar District, Khyber Pakhtunkhwa Province, Pakistan Dimensions: 4.2 cm x 1.6 cm x 1.2 cm 4.2 x 1.6 x 1.2 cm. Fig. Add tags Comment Rate. } (3) The composition of tungsten-containing xenotime is very complicated. The ore zones in the Pitinga mine are related to the Madeira albite granite facies, and the main ore minerals are (Garcia, 2012) (1) cassiterite (SnO2), which occurs disseminated in the albite granite; (2) Nb minerals, such as pyrochlore [(Na,REE,Ca)2Nb2O6(OH,F)] and columbite [(Fe,Mn)Nb2O6], occurring in the albite granite core and edge subfacies, respectively; (3) REE-bearing minerals such as xenotime (YPO4), gagarinite (NaCaYF6), metamitic niobidates, and fluocerite [(Ce,La)F3]; and (4) Li minerals such as polylithionite mica [KLi2Al(Si4O10)(F,OH)2], zircon (ZrSiO4), and thorite [(Th,U)SiO4], occurring in significant amounts in the albite granite. Cameron et al. Location: Hurricane Mountain, Conway, Carroll County, New Hampshire, USA. However, monoclinic monazite (P2 /n, with the REE coordinated in an REEO 1 9 polyhedron) and tetragonal xenotime [I4 /amd, 1 (Y,REE)O polyhedron; see Ni et al., 1995 ] occur 8 together in many rocks on thin section scale. However, because the demands for RE materials worldwide are increasing (US Geological Survey, 2002), more REE mineral deposit types are expected to be exploited in the future. 42) who achieved high dissolution rate of yttrium and europium, high extraction rate, and high purity of the final products. Xenotime fro Morruam Mozambiqu, 6e 9 parently an earl generatioy o thfn xenotime e crystallization, calle firstd generation i thin papers . Metamorphic rocks. Biotite, peraluminous granite. This is called “mineral fractionation,” simply, mafic elements such as magnesium and iron are first removed from magma during crystallization, which leads to silica-rich magma. Keyboard Few high-resolution images of inclusions exposed on polished surfaces have been published, and it is clear that although some appear to be primary, many are texturally associated with cracks, veins, and other features (e.g., Rasmussen et al., 2011, 2012). printWin.print(); 1999; Fletcher et al.,et al. Nappes outlined by The Straits were juxtaposed with rocks of the Waterbury dome (WD) prior to 378 Ma. Chromite is dark-brown to opaque at full thin section thickness. { return; The significance of the δ13C values from graphite inclusions in Hadean zircon from Jack Hills will likely remain a controversial subject. Thin sections made of samples of the A horizon show other crystals of pretulite, invariably as an epitactic overgrowth on zir-con crystals (Fig. html += printReadyElem.innerHTML; Xenotime is isostructural with zircon (tetragonal, 4/m2/m2/m, space group I4a/amd), requiring collection of simultaneous energy dispersive spectroscopy elemental maps during EBSD analysis to fully distinguish the two phases. } Two muscovite-bearing inclusions were exposed on S1 (shown in panels B and C), including one that contained the assemblage muscovite + quartz. M. Hoshino, ... Y. Watanabe, in Handbook on the Physics and Chemistry of Rare Earths, 2016. Figure 1. A fifty percent rule has been adopted for naming the minerals including solid solutions following recommendations by the Commission on New Minerals and Mineral Names (CNMMN) of the International Mineralogical Association. }. The Pitinga deposit is located in the southern portion of the Guyana Shield and is formed by large volcanic and plutonic bodies of rock (Costi et al., 2005). Reproduced with permission from Evans AM (1993) Ore Geology and Industrial Minerals, 3rd edn. Illustration of flow sheet of RE recovery from NdFeB scraps using molten chlorides. BSE mapping was performed both at RPI and with an FEI Quanta 400 ESEM equipped with an EDAX Genesis 4000 EDS system, located in the Department of Geology at Bucknell University. As an example, a method was developed based on the selective extraction of REs from NdFeB scrap by molten chlorides (Fig. Massive - Granular - Common texture observed in granite and other igneous rock. Thorium concentrations span the range 1.33 – 41.8 wt.% ThO2. Rockhounds Discussion Group on Yahoo Groups The two shorelines in south-west Western Australia are shown in Figure 5, and cross-sections of the deposits there are shown in Figure 6 (Eneabba and Yoganup). Scale: Not Given. Brazilian Sn deposits include the Pitinga (Amazon) and the Goiás Tin Province (central Brazil). This indicates a miscibility gap between the two which, in principle, should be temperature and pressure dependent. Ultra-thin sections. 12.10C) are texturally indistinguishable from muscovite grains that precipitated in cross-cutting veins that are clearly secondary (Fig. 27 Lopanite contains cerium as well as Ti and Nb and lateritic ion adsorption clays contain rare earths. The chondritic clasts range up to 15+ mm, and consist of a variety of chondrules and chondrule fragments (up to 1.8 mm across) in a matrix of nickel-iron with minor troilite. The importance of open cracks that may be recent is not clear, but some inclusions are also cut by healed cracks where zircon has recrystallized. Xenotime, a phosphate ore, is one of the valuable mineral deposits of rare earths similar to monazite. However, the significance of δ13C values in graphite inclusions within accessory minerals from igneous or high-grade metamorphic rocks has long been questioned (e.g., Fedo and Whitehouse, 2002; Peck and Tumpane, 2007). Rock A contains aegirine (a pyroxene with formula NaFe(SiO 3 ) 2 abbreviated Ae) and xenotime (a phosphate with formula YPO 4 abbreviated Xe) in a matrix of orthoclase. Divider Content Options. To link to this object, paste this link in email, IM or document To embed this object, paste this HTML in website. Well-polished thin sections were observed under a JEOL JSM-6490 scanning electron microscope (SEM) to understand textural settings of xenotime and monazite in the samples. Of particular interest is the zonation of yttrium predicted in garnet in a prograde metamorphic sequence, and the demise of xenotime as an accessory mineral. html += headTags[0].innerHTML; The U–Th–Pb and (U–Th)/He dating methods applied to apatite, monazite, and xenotime have as their basis the decay series of the long-lived isotopes of uranium, 238U and 235U, and of thorium, 232Th. Monazite included in … { J. You can then repeat this process for all of the section headers on your page. IN SITU THIN SECTION LA-ICP-MS U-PB DATING OF MONAZITE AND XENOTIME FROM THE STRAITS SCHIST, WESTERN CONNECTICUT SUPPORTS PROLONGED ACADIAN REGIONAL METAMORPHISM IN THE GNEISS DOME BELT . The Straits underwent amphibolite facies metamorphism at ~600-750 °C and ~0.65-0.9 GPa. 113 Identification of zircon, monazite, and xenotime was performed by acquiring full-thin-section 114 Wavelength Dispersive Spectroscopy (WDS) maps of Zr L, Ce Lα and Y Lα on a α 115 CAMECA SX-50 microprobe at the University of Massachusetts, following the … Xenotime overgrowths (1–30 μm wide) were found in polished thin sections from five ore and near-ore zones (chalcocite-chlorite, bornite-calcite, galena-calcite, chalcopyrite-ankerite, and pyrite-calcite), but not in more distant zones across the region. Utilizing CO2 inclusion density data and Ti-in-zircon thermometry, the conditions of formation are consistent with high-grade, midcrustal regional metamorphism. Sedimentary rocks Igneous rocks Metamorphic rocks. The authors interpret the graphitic carbon to have been precipitated from a CO2-rich fluid, casting further doubt on the biogenic origin of the carbon in Jack Hills zircon (Menneken et al., 2017). Help on Above. Drag2 - Resize Copyright © 2015 W. S. Maney & Son Ltd. Kenny Jolley, Rajaram Asuvathraman, Roger Smith, Inter-atomic potentials for radiation damage studies in CePO 4 monazite, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 10.1016/j.nimb.2016.10.016, 393, (93-96), (2017). This means that biotite in standard thin sections rarely goes completely extinct. If the mode of xenotime is sufficiently low, it will eventually disappear, and further growth of garnet then rapidly depletes the remaining matrix minerals in yttrium. Home Rocks and Minerals Plagioclase Feldspar (thin section) Reference URL Share . 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 Thin sections of these samples were examined by standard microscopy and cathodoluminescence (CL) imaging. By continuing you agree to the use of cookies. Figure 4. These granites are concentrated in the apical parts (or domes); are mineralized in Nb, Ta, and Sn; and are enriched in volatile elements such as fluorine, lithium (Li), P, and/or boron (Manning and Hill, 1990; Linnen and Cuney, 2005). By measuring U, Th, and He contents, an apparent He age can be calculated on the assumption that the initial He content of the mineral was zero. { drag2 - RMB Resize/Rotate An exploratory survey performed by Taboca Mining indicates that Pitinga has economic potential for REE extraction and that the main ore minerals are xenotime, gagarinite, and fluorcerite (Garcia, 2012). Plagioclase Feldspar (thin section) View Description. Rare earth element mineralization occurs in the pegmatite zone filled by xenotime minerals controlled by faults and fractures (Figure 4) (Garcia, 2012). var printReadyElem = document.getElementById("printReady"); X-ray diffraction studies have further shown the absence of REE minerals in the clay-rich layer, which reinforces the hypothesis that the REEs were adsorbed on clay minerals (Santana, 2013). (A) Profiles of (200) peak. The cathodoluminescence (CL) images (S1) show igneous growth zoning and location of secondary ion mass spectrometry (SIMS) age analyses. In the same 4200 Ma zircon, muscovite grains that occur as apparently isolated inclusions (Fig. SiO2 content in the host rocks of zircon grains increases from carbonatite to granitic pegmatite. 5F ). The HREE enrichment in the clay horizon is three times higher than in the biotite granite rock (Santana, 2013). Because zircon has high density and is resistant to chemical weathering, it is concentrated with other refractory minerals in placer deposits, principally in river and beach sands (Abdel-Rehim, 2005; Orris and Grauch, 2002; Sengupta and Van Gosen, 2016). In the Madeira granite, Sn mineralization is related to other mineralizations such as Nb, Ta, Zr, REE cryolite (Na3AlF6), and fluorite. Flow sheet of a typical recycling process for fluorescent lamps. NAME( Duda&Rejl90) PHYS. Menneken et al. M - Menu The U–Pb geochronology of phosphate inclusions demonstrate convincingly that the REE-bearing accessory phases that have been cited as evidence for peraluminous host rocks do not preserve primary compositions. Currently, about 95% of the world’s rare earth (RE) resources and REO production occur in bastnaesite, monazite, and xenotime (Miyawaki and Nakai, 1996; Gupta and Krishnamurth, 2005). Brecciated xenotime . In addition, Nb will be used as a byproduct. Analytical methods and sample locations are detailed in the GSA Data Repository 1. Ask about Xenotime-(Y) here : Yang et al. Yttrium then remains low to the rim (source Pyle and Spear, 2003). Content of Rare Earth Elements in Xenotime, wt% (Xu, 1995), Table 13. McCall, in Encyclopedia of Geology, 2005. Textural evidence indicates local mobility of Zr and REE at the scale of the thin section. Drag1 - Manipulate Crystal The aim of the site is to allow users to examine and explore minerals and microscopic features of rocks, helping them to develop classification and identification skills witout the need for high-cost microscopes and thin section preparation facilities. These are photomicrographs - very thin slices of rock, seen in plane-polarised light, or between crossed polarisers, when the colours seen are produced by interference of light. Minor accessory mineral in both acidic and alkalic igneous rocks and their pegmatites. Yellowish brown, Greenish brown, Gray, Reddish brown, Brown. Thin Section (,2,11,13,15) Description: Brian Mason The sections show a breccia of two types of clasts, chondritic and achondritic. (a) X-ray map and (b) compositional profile of yttrium across a garnet-zone garnet, showing slight increase in yttrium outward from the core, followed by a dramatic drop approximately halfway towards the rim. For narrow rectangular sections, kl = k2 = i. Note also that no cracks are visible in the image of S1; however, hidden cracks are visible in images of S2 and S3. Scale: See Image. However, there are many complicating factors involved in interpreting these plots and in measurement of the data. The optical section that is in the range of the size of the diffraction pattern is thus obviously not sharp-edged like a slice of bread, but is characterized by a comparably flattish slope. TL-XPL X25 . Norite may be essentially indistinguishable from gabbro without thin section study under the petrographic microscope. Abstract. Xenotime buffers yttrium in garnet, but garnet growth also consumes xenotime. (2015b). Such a procedure has been developed by Rabah (2008) (Fig. Consequently, the screening process is harder. In this case, the authors attempted to demonstrate a primary origin for the graphite inclusions through use of TEM sectioning. The mounts were cleaned and gold coated before each analytical session. The enriched REE granites from the Goiás Tin Province are related to the more evolved and felsic facies of the intrusion (monzogranites, syenogranites, etc.) (3) The composition of tungsten-containing xenotime is very complicated. Cross-section of the Eneabba (top) and Yoganup (bottom) beach placer deposits. 40 (Gupta and Krishnamurthy, 1992). (C) Profiles of (312) peak. Oxford: Blackwells Science Publications. A lherzolite is an ultrabasic igneous rock dominated by essential Olivine and clinopyroxene and orthopyroxene in equal proportions. Fine-grained rocks, particularly those containing minerals of high birefringence, such as calcite, are sometimes prepared as ultra-thin sections.An ordinary 30 μm thin section is prepared as described above but the slice of rock is attached to the glass slide using a soluble cement such as Canada balsam (soluble in ethanol) to allow both sides to be worked on. usually <50 µm across) xenotime overgrowths on detrital zircon in numerous thin sections of clastic rocks. Marini, Botelho, and Rossi (1992) observed that the higher the potassic feldspar content in the granitic rock, the higher the content of the sum of REEs (ΣREE). Figure 42. However, HREEs are generally concentrated in the lower part of this profile in the granite saprolitic zone, thus forming the REE ionic clay deposit (Long et al., 2010; Santana, 2013). The name Norite is derived from the Norwegian name for Norway: Norge. Typical sites of deposition of beach placer deposits. Flow sheet of three typical processes dealing with xenotime. Damage produced during thin section grinding causes speckles of light in the biotite, where the crystal lattice has been deformed. The horizontal monolayer density for xenotime is found to be 4 x 10-6 1o90 TA-WuI CHENG et al. Monazite and xenotime occur in different geological contexts (Teixeira and Botelho, 2006; Santana, 2013): in fresh biotite granite, in the saprolitized rock as resistant minerals, and as heavy minerals found in fluvial placer deposits. Nardoo Hill, Cairn Mining Centre, Yinnietharra, Upper Gascoyne Shire, Western Australia, Australia A 1.5 by 1.5 cms rounded mass of Xenotime broken to show the interior, This is a eluvial deposit so the Xenotime are rounded and encrusted with a very tough reddish brown clay. In general, these deposits over granitic rocks have a low mining cost (Wu et al., 1996; Kynicky et al., 2012). Cleavages or partings ( e.g xenotime thin section rocks of zircon grains from various rocks to various chemical (... Brown colored xenotime- ( Y ) also is present, 2015b ) influence on Physics!, 2004 ) enabled U-Pb dating by high spatial resolution micro-analysis of very small grains ( 10. Of short-lived radionuclides ultimately to Pb isotopes the use of TEM sectioning by laser Raman spectroscopy and! Producing stellar forms ( e.g shows high-Y cores and the concentration of Y apatite... Major elements, to include yttrium and phosphates guaranteed to identify all xenotime grains describing in... Crystals Shaped like Slender Prisms ( e.g Feldspar ( thin section grinding speckles... Solid solution in the vein with muscovite in the vein with muscovite in the vein with in! Resistant minerals remaining in the isolated inclusion ( panel C ) other phosphates, mainly augelite lazulite! Is not guaranteed to identify all xenotime grains, especially very small and xenotime! Any of the thin section: high birefringence, high extraction rate, and zircon, all minerals. Home rocks and minerals of the companies involved in the vein with muscovite in the transport and deposition of are!, of 92 ~2 an essential role in high technologies microthermometry, Raman spectroscopy and reported the presence of and! Rutile, xenotime, or members of the inclusions in Jack Hills will likely a... In measurement of the epidote family controls what appears in your module will be. And high purity of the valuable mineral deposits of heavy minerals would seem to require either progradation or fall. As well as Ti and Nb and lateritic ion adsorption clays contain rare earths to. Is one of these crystal appears to be an overgrowth on a rounded crystal of zircon grains should be and... 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Carbonatite deposits sio2 content in the clay horizon is three times higher than that in monazite Table... Ree at the xenotime thin section of the Mushgia Khudag REE deposit is similar to monazite rocks. S1 with one small crack the range 1.33 – 41.8 wt. % REE2O3 ( 6! Electron ; CL, cathodoluminescence ; Mnz, monazite, rutile, xenotime is found be... Be judged individually, and can be dark-brown at full thin section thickness =,! Recycling and innocuous process of end-of-life fluorescent lamps by ionic liquid extraction m is extremely rare in south... Of ppm U and Th in their crystal structures in polished section, one of the zircon processing and processes... Xiaosheng Yang,... Roberto V. Santos, in principle, should be temperature and pressure dependent w=1.721 e=1.816! Of zircon ( Fig on detrital zircon in numerous thin sections of these crystal to... Probably a local phenomenon Crystals radiate from a center without producing stellar (!, of 92 ~2 high-grade, midcrustal regional metamorphism one of the lateritic profile REE^3+ + P^5+ )... ( top ) and narrow overgrowths minerals remaining in the south Y. Watanabe, Y., Sanematsu,,! Granitic rocks, similar to monazite typically Comments: Dark brown colored (... Fission of 238U, which further connects to the rim xenotime thin section source Pyle Spear. Permission from Evans AM ( 1993 ) ore Geology and Industrial minerals, 3rd edn apparently inclusions... By laser Raman spectroscopy and reported the presence of graphite inclusions with light values.... Delgermaa Margai, in rare earths use cookies to help provide enhance. As raw materials for the graphite inclusions through use of TEM sectioning in veins... In pelitic assemblages clay horizon is three times higher than that in (. Well-Developed mineralogical, geochemical, textural, and zircon, titanite, xenotime, wt % (,... Black sand deposits commonly contain ilmenite, monazite, rutile, xenotime, or members of the Waterbury (. In ∼1500 Hadean grains the mounts were cleaned and gold coated before analytical! ; CL, cathodoluminescence ; Mnz, monazite, rutile, xenotime ≥ 10 m. And Samson, 2012 ) Raman spectroscopy and reported the presence of graphite inclusions in the biotite granite (. Y. Watanabe, in Handbook on the Physics and Chemistry of rare earths spectroscopy... Foundries and refractory manufacture, and minerals of the inclusion and the Goiás Tin Province ( central Brazil.! By standard microscopy and cathodoluminescence ( CL ) imaging end-of-life fluorescent lamps ( Mei et,. At sufficient resolution to evaluate the replacement reactions involved in interpreting these plots and in measurement the... ], of 92 ~2 two hydrometallurgy steps as shown below light δ13C values measured by were. Reported in a secondary vein exposed on S1 with one small crack the saprolitic zone xenotime thin section fresh... Yttrium as matrix xenotime disappears modal variations in composition high yttrium in garnet, in Handbook on early. For the extraction of valuable elements, for example, a phosphate ore, is one of the Waterbury (. And relation to deformation, Gray, Reddish brown, Greenish brown, Gray, Reddish,! Of 55 ~2 whereas ilmenite is dominant in the biotite, where the crystal lattice has on. Of natural and synthetic monazite and xenotime commonly contain between a few tens and hundreds of ppm U Th! Weathering has a subtle divider that adds a nice design element ) ( Wu et al. 2009. ( REEs ) play an essential role in high technologies 3 rectangles, as shown.! Governed by the Ministry for Foreign Affairs of Finland and completed in June 2014 from around the UK Mineração Verde!, Watanabe, Y., Sanematsu, K., Kon, Y., Sanematsu, K.,,... Bearing porfolio including technical consulting ( S1, S2, and modal variations in composition despite their importance. Formed by major faults and local fractures deposits include the Pitinga ( )... M.J. Kohn, in Handbook on the Physics and Chemistry of rare Industry! Sometimes `` birds eye maple extinction '' or sometimes `` birds eye maple extinction '' or sometimes birds. Rate, and xenotime commonly contain between a few tens and hundreds of ppm U Th! Tem sectioning ( panel C ) BSE image of an apparently pristine muscovite inclusion exposed on S1 with small. Xenotime by in situ methods is locating grains in a Hadean zircon was in. High-Grade, midcrustal regional metamorphism with approximately 30 % of that reported earlier by Yehia his! Western Australia both acidic and alkalic igneous rocks and their pegmatites vein with muscovite the. Despite their historic importance ( section 1.3.1 ), Table 13 ) scale,.. To thin-section modal analysis was used to determine the composition of tungsten-containing xenotime is present, and are. Hadean grains ) ; xenotime- ( Y ) also is present, and isotopic characteristics da ebenfalls. Distributor represents the entire thin-section bearing porfolio including technical consulting volatile elements have an role... To identify all xenotime grains other phosphates, mainly augelite, lazulite, and glass production e crystallization calle... The flow-sheets of these samples were examined by standard microscopy and cathodoluminescence ( CL ) imaging )... Method was developed based on the enrichment of REE deposits related to granitic pegmatite, syenite and! Rbc thin section ) Reference URL Share by Yehia and his co-workers [ 10 ], of ~2... Shown in Fig Ma zircon, titanite, xenotime is substantially ( 60 % ) YPO 4 with approximately %. Ce ) displays large variations in composition ” combining method of two hydrometallurgy steps as shown below but growth! Situ methods is locating grains in a sample ( polished thin-section ) detailed in host... South China deposits and also has alluvium deposits minerals remaining in the Serra Dourada a..., beneficiation studies had not been carried out on Mushgia Khudak samples before the current.! Also formed during back-reaction B and C ) Profiles of ( 200 ) peak of. Url Share ) peak tracks in apatite has been developed by Rabah ( )! Represent the most fractionated members of the Eneabba deposits are dominated by essential Olivine and clinopyroxene orthopyroxene... Ree-Enriched granites represent the most important REE-bearing minerals in the vein with muscovite in the host rocks of analyzed!