Vibrational Spectroscopic Characterization of the Phosphate Mineral Series Eosphorite-Childrenite-(Mn,Fe)Al(PO4)(OH)2.(H2O)

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Frost, Ray, Xi, Yunfei, Scholz, Ricardo, Lopez, Andres, Fernandes Lima, Rosa Malena, & Ferreira, Claudiane Moraes (2013) Vibrational spectroscopic characterization of the phosphate mineral series eosphorite-childrenite-(Mn,Fe)Al(PO4)(OH)2.(H2O). Vibrational Spectroscopy, 67, pp. 14-21.

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childrenite – (Mn,Fe)Al(PO4)(OH)2·(H2O)

Ray L. Frosta, Yunfei Xia, Ricardo Scholzb, Claudiane Moraes Ferreirab

a School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001, Australia.

b Geology Department, School of Mines, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, MG, 35,400-00, Brazil

Abstract:

The phosphate mineral series eosphorite-childrenite – (Mn,Fe)Al(PO4)(OH)2·(H2O) has been studied using a combination of electron probe analysis and vibrational spectroscopy. Eosphorite is the manganese rich mineral with lower iron content in comparison with the childrenite which has higher iron and lower manganese content. The determined formula of the minerals are (Mn0.71,Fe0.13,Ca0.01)(Al)1.03(PO4)1.07(OH1.85,F0.02)·2(H2O) and

(Fe0.49,Mn0.35,Mg0.06,Ca0.04)(Al)1.03(PO4)1.05(OH)1.80·2(H2O). Raman spectroscopy enabled the observation of bands at 969, 978 and 1011 cm-1 assigned to monohydrogen phosphate, phosphate and dihydrogen phosphate units. Differences are observed in the area of the peaks between the two eosphorite minerals. -1 Raman bands at 562, 595, and 608 cm are assigned to the ν4 out of plane bending modes of -1 the PO4, HPO4 and H2PO4 units; Raman bands at 405, 427 and 466 cm are attributed to the

ν2 modes of these units. Raman bands of the hydroxyl and water stretching modes are observed.

Key words: eosphorite, childrenite, phosphate, pegmatite, Raman spectroscopy, infrared spectroscopy

 Author to whom correspondence should be addressed ([email protected]) P +61 7 3138 2407 F: +61 7 3138 1804 1

Introduction

Eosphorite is a pink manganese mineral with formula MnAl(PO4)(OH)2·(H2O) which crystallises in a monoclinic crystal system [1] and forms prismatic crystals which form radiating clusters. The mineral shows pseudo-orthrhombic morphology due to twinning. The mineral ocurs worldwide in pegamatites [2-7] and is always associated with other phosphate minerals [8].

Eosphorite forms a solid solution series with the mineral childrenite [9-11]. Childrenite's formula is (Fe, Mn)AlPO4(OH)2·H2O and differs from eosphorite by being rich in iron instead of manganese. The structures of the two minerals are the same and therefore it would be expected that their differences in physical properties between the two would be related to the iron/manganese content. Eosphorite is less dense and is generally pinkish to rose-red in color whereas childrenite's colors tends towards various shades of brown. In terms of crystal habits the two also differ. Eosphorite forms prismatic, slender crystals and rosettes. Childrenite forms tabular or bladed individuals or lamellar aggregates. It has been said that the two different habits belie their solid solution relationship.

In this work, samples of the mineral series eosphorite and childrenite from different pegmatites from Minas Gerais were studied. Characterization include chemistry via Electron Probe Microanalysis in the WDS mode (EPMA) and spectroscopic characterization of the structure with infrared and Raman.

Experimental Samples description and preparation The eosphorite and childrenite samples studied in this work were obtained from the collection of the Geology Department of the Federal University of Ouro Preto, Minas Gerais, Brazil, with sample code SAA-090 and SAA-072 respectively. The samples are from two different granitic pegmatites from Minas Gerais, Brazil.

Sample SAA-072 was collected from the Ponte do Piauí mine, located in the Piauí valley, municipality of Itinga. The region is well-known as an important source of rare phosphates

and gemological minerals. The pegmatite is located in the Araçuaí pegmatite district, one of the subdivisions of the Eastern Brazilian Pegmatite province [12]. The pegmatite is mined for gemstones and samples for the collectors market. It is heterogeneous with well-developed mineralogical and textural zoning. The primary mineral association is represented by quartz, muscovite, microcline, schorl and almandine-spessartine. The secondary association is mainly composed by albite, Li bearing micas, cassiterite, elbaite and hydrothermal rose quartz. In the Ponte do Piauí pegmatite, secondary phosphates, namely childrenite, eosphorite, fluorapatite, zanazziite, occur in miarolitic cavities in association with albite, quartz and muscovite. Childrenite grows usually along the surface of quartz crystals and in albite agregates.

Sample SAA-090 was collected from Roberto mine, a granitic pegmatite located in Divino das Laranjeiras east of Minas Gerais. The region is situated 65 km ENE of Governador Valadares. The region is well-known as an important source of rare minerals such as brazilianite. The pegmatite is located in the Conselheiro Pena pegmatite district, also one of the subdivisions of the Eastern Brazilian Pegmatite province (EBP). The pegmatite is mined for rare minerals for the collectors market. It is heterogeneous with well-developed mineralogical and textural zoning. The primary mineral association is represented by quartz, muscovite, microcline, schorl, almandine-spessartine and triphylite. The secondary association is mainly composed by albite, quartz crystals and a number of secondary phosphates, namely eosphorite, fluorapatite, zanazziite and brazilianite. The phosphates occur in miarolitic cavities.

The sample was gently crushed and the associated minerals were removed under a stereomicroscope Leica MZ4. The eosphorite and childrenite samples were phase analyzed by X-ray diffraction. Scanning electron microscopy (SEM) was applied to support the mineralogical chemical

Scanning electron microscopy (SEM) Experiments and analyses involving electron microscopy were performed in the Center of Microscopy of the Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil (http://www.microscopia.ufmg.br). Eosphorite and childrenite single crystals were coated with a 5 nm layer of evaporated Au. Secondary Electron and Backscattering Electron images were obtained using a JEOL JSM- 3

6360LV equipment. Qualitative and semi-quantitative chemical analysis in the EDS mode were performed with a ThermoNORAN spectrometer model Quest and was applied to support the mineral characterization and to determine the major elements to be measured by Electron probe micro-analysis.

Electron probe micro-analysis (EPMA) The quantitative chemical analysis of eosphorite and childrenite single crystals was carried via EPMA. The chemical analysis was carried out with a Jeol JXA8900R spectrometer from the Physics Department of the Federal University of Minas Gerais, Belo Horizonte. For each selected element was used the following standards: Fe and Mg – olivin, Mn – rodhonite, P and Ca - Apatite Artimex, Al - Corundum and F - Fluorite. The epoxy embedded eosphorite and childrenite crystals was polished in the sequence of 9μm, 6μm and 1μm diamond paste MetaDI® II Diamond Paste – Buhler, using water as a lubricant, with a semi-automatic MiniMet® 1000 Grinder-Polisher – Buehler. Finally, the epoxy embedded samples was coated with a thin layer of evaporated carbon. The electron probe microanalysis in the WDS (wavelength dispersive spectrometer) mode was obtained at 15 kV accelerating voltage and beam current of 10 nA. Chemical formula was calculated on the basis of seven oxygen atoms

(O, F, OH, H2O).

Raman microprobe spectroscopy Crystals of eosphorite were placed on a polished metal surface on the stage of an Olympus BHSM microscope, which is equipped with 10x, 20x, and 50x objectives. The microscope is part of a Renishaw 1000 Raman microscope system, which also includes a monochromator, a filter system and a CCD detector (1024 pixels). The Raman spectra were excited by a Spectra-Physics model 127 He-Ne laser producing highly polarised light at 633 nm and collected at a nominal resolution of 2 cm-1 and a precision of ± 1 cm-1 in the range between 200 and 4000 cm-1. Repeated acquisitions on the crystals using the highest magnification (50x) were accumulated to improve the signal to noise ratio of the spectra. Raman Spectra were calibrated using the 520.5 cm-1 line of a silicon wafer. The Raman spectrum of at least 10 crystals was collected to ensure the consistency of the spectra.

Infrared spectroscopy Infrared spectra were obtained using a Nicolet Nexus 870 FTIR spectrometer with a smart endurance single bounce diamond ATR cell. Spectra over the 4000525 cm-1 range were 4

obtained by the co-addition of 128 scans with a resolution of 4 cm-1 and a mirror velocity of 0.6329 cm/s. Spectra were co-added to improve the signal to noise ratio.

Spectral manipulation such as baseline correction/adjustment and smoothing were performed using the Spectracalc software package GRAMS (Galactic Industries Corporation, NH, USA). Band component analysis was undertaken using the Jandel ‘Peakfit’ software package that enabled the type of fitting function to be selected and allows specific parameters to be fixed or varied accordingly. Band fitting was done using a Lorentzian-Gaussian cross-product function with the minimum number of component bands used for the fitting process. The Gaussian-Lorentzian ratio was maintained at values greater than 0.7 and fitting was undertaken until reproducible results were obtained with squared correlations of r2 greater than 0.995.

Results and discussion Chemical characterization

The quantitative chemical analysis of eosphorite and childrenite is presented in Table

1. H2O content was calculated by stoichiometry and the chemical formula was calculated on

the basis of 7 O atoms (O, F, OH, H2O). The chemical composition indicates a Mn rich phase for the sample SAA-090 with partial substitution of Fe. Chemical formula for SAA-090 can

be expressed as: (Mn0.71,Fe0.13,Ca0.01)(Al)1.03(PO4)1.07(OH1.85,F0.02)·2(H2O). For the sample SAA-072, chemical composition indicates a intermediate member of the childrenite- eosphorite serie with predominance of the Fe phase. The chemical formula can be expressed

as: (Fe0.49,Mn0.35,Mg0.06,Ca0.04)(Al)1.03(PO4)1.05(OH)1.80·2(H2O).

Vibrational spectroscopy background

In aqueous systems, the Raman spectra of phosphate oxyanions show a symmetric stretching -1 -1 mode (ν1) at 938 cm , an antisymmetric stretching mode (ν3) at 1017 cm , a symmetric -1 -1 bending mode (ν2) at 420 cm and a ν4 bending mode at 567 cm [13-15]. S.D. Ross in Farmer (page 404) listed some well-known minerals containing phosphate which were either hydrated or hydroxylated or both [16]. The vibrational spectrum of the dihydrogen phosphate -1 anion has been reported in Farmer. The PO2 symmetric stretching mode occurs at 1072 cm and the POH symmetric stretching mode at ~878 cm-1. The POH antisymmetric stretching

-1 -1 -1 mode was at 947 cm and the P(OH)2 bending mode at 380 cm . The band at 1150 cm was assigned to the PO2 antisymmetric stretching mode. The position of these bands will shift according to the crystal structure of the mineral.

The vibrational spectra of phosphate minerals has been published by S. D. Ross in Farmer’s treatise Chapter 17 [16]. The Table 17.III reports the band positions of a wide range of phosphates and arsenates [16]. The band positions for the monohydrogen phosphate anion of -1 disodium hydrogen phosphate dihydrate is given as ν1 at 820 and 866 cm , ν2 at around 460 -1 -1 -1 cm , ν3 as 953, 993, 1055, 1070, 1120 and 1135 cm , ν4 at 520, 539, 558, 575 cm . The POH unit has vibrations associated with the OH specie. The stretching vibration of the POH units was tabulated as 2430 and 2870 cm-1, and bending modes at 766 and 1256 cm-1. Water stretching vibrations were found at 3050 and 3350 cm-1. The position of the bands for the disodium hydrogen phosphate is very dependent on the waters of hydration. There have been several Raman spectroscopic studies of the monosodium dihydrogen phosphate chemicals [17-21].

Spectroscopy The Raman spectrum of eosphorite and childrenite in the 100 to 4000 cm-1 spectral range is displayed in Figure 1. This figure shows the peak positions and relative intensity of these bands. The intensity in the phosphate stretching region is greater than the intensity of the OH spectral region. The infrared spectrum of eosphorite in the 500 to 4000 cm-1 spectral region is reported in Figure 2. This figure displays the peak position and their relative intensity of these peaks. It is observed that large parts of the spectrum show no or little intensity. Thus, the spectrum is subdivided into sections depending upon the type of vibration being observed.

The Raman spectrum of eosphorite (sample SAA-090) and childrenite (sample SAA-072) in the 800 to 1400 cm-1 spectral range is shown in Figure 3. Intense peaks for eosphorite are observed at 969, 978 and 1011 cm-1. These bands are attributed to the stretching vibrations of the PO stretching vibrations. It is possible to distinguish the different types of phosphates in -1 3- the eosphorite structure. The band at 978 cm is assigned to the PO4 PO stretching -1 2- vibration. The band at 969 cm is attributed to the PO stretching vibrations of the HOPO3 -1 - units, whilst the band at 1011 cm is ascribed to the PO stretching vibration of the (HO)2PO2 units. By measuring the area of the peaks, an estimate of the ratio of the different phosphate

3- 2- units can be made. The ratio of the phosphate PO4 , monohydrogen phosphate HOPO3 , - dihydrogen phosphate (HO)2PO2 peaks is 13.1/7.9/15.4. These figures imply that there is about an equal ratio of phosphate and dihydrogen phosphate in the mineral structure and significantly less of the monohydrogen phosphate.

-1 The low intensity Raman bands at 1091, 1142 and 1183 cm are assigned to the phosphate ν3 antisymmetric stretching modes. There appears to be very little difference in the spectrum of eosphorite sample SAA-90 (Mn rich) and the spectrum of SAA-72 (Fe rich). However, the 3- 2- ratio of the phosphate PO4 , monohydrogen phosphate HOPO3 , dihydrogen phosphate - (HO)2PO2 peaks is different for the Fe rich mineral. The ratio works out to be 7.2, 13.1 and 8.4. These values suggest that there is significantly more of the monophosphate units present. Low intensity Raman bands at 816 and 864 cm-1 may be assigned to the water librational modes.

- Galy [19] first studied the polarized Raman spectra of the H2PO4 anion. Choi et al. reported

the polarization spectra of NaH2PO4 crystals. Casciani and Condrate [22] published spectra on brushite and monetite together with synthetic anhydrous monocalcium phosphate

(Ca(H2PO4)2), monocalcium dihydrogen phosphate hydrate (Ca(H2PO4)2·H2O) and

octacalcium phosphate (Ca8H2(PO4)6·5H2O). These authors determined band assignments for -1 Ca(H2PO4) and reported bands at 1002 and 1011 cm as POH and PO stretching vibrations, respectively. The two Raman bands at 1139 and 1165 cm-1 are attributed to both the HOP and PO antisymmetric stretching vibrations. Casciani and Condrate [22] tabulated Raman bands at 1132 and 1155 cm-1 and assigned these bands to P-O symmetric and the P-O antisymmetric stretching vibrations.

The infrared spectrum of eosphorite is portrayed in Figure 4. The infrared spectrum displays greater complexity with multiple overlapping bands. The complexity of the spectrum makes it difficult to undertake band assignments. There is a difference between taking a Raman spectrum and an infrared spectrum. The sample spot size of the Raman spectrometer is around 1 micron. In infrared spectroscopy the measurement size is at best 30 microns. Thus in Raman spectroscopy it is possible to collect data for a pure mineral because that crystal was selected. It is more likely that the infrared spectrum is more likely to collect data for a mixture. This is why of course it is an advantage to run the Raman spectrum. Infrared bands are observed at 900, 940, 982, 1028 cm-1 and are assigned to the phosphate symmetric 7

stretching modes. The infrared bands at 1078, 1098, 1162 and 1186 cm-1 are attributed to the -1 ν3 antisymmetric stretching modes. The infrared bands at 802 and 843 cm are due to water librational modes. The infrared bands at 659, 680 and 696 cm-1 are due to phosphate bending modes.

Infrared bands for the mineral dittmarite (NH4)MgPO4·H2O are found at 978, 1063 and 1105 -1 cm (this work). Choi et al. [18] published spectra of NaH2PO4; however these authors did not tabulate or mark the position of the peaks. Therefore, it is very difficult to make any comparison of the peak positions of archerite and that of published data by Choi et al. Casciani and Condrate [22] reported bands assigned to these vibrational modes for -1 -1 Ca(H2PO4)2 at 876 and 901 cm . The infrared bands at 728, 826 cm are attributed to the 2- POH deformation modes of the HOPO3 units.

The Raman spectrum of eosphorite in the 300 to 800 cm-1 spectral range is shown in Figure 5. Three spectral regions in this figure may be distainguished. The first region is between 550 and 650 cm-1 with Raman bands observed at 562, 595, and 608 cm-1. These bands are

attributed to the ν4 out of plane bending modes of the PO4 and H2PO4 units. The Raman -1 spectrum of crystalline NaH2PO4 shows Raman bands at 526, 546 and 618 cm (this work). The second spectral component is the region centred upn 466 cm-1 with shoulder bands on the -1 low wavenumber side at 405 and 427 cm . These bands are attributed to the ν2 PO4 and

H2PO4 bending modes. The Raman spectrum of NaH2PO4 shows Raman bands at 460 and 482 cm-1. The third aspect is the Raman bands at 310 and 347 cm-1. These bands are duie to MO stretching vibrations.

The far low wavenumber region is displayed in Figure 6. Considerbale variation in both band position and intensity is found. Considerbale differences are observed in this spectral region. Simply put, the bands may be described as lattice vibrations.

The Raman spectrum of samples SAA-090 and SAA-072 in the 2600 to 3800 cm-1 spectral range are shown in Figure 7. Two features are observed: (a) an intense sharpish band at around 3460 cm-1 and broad bands centred upon 3063 and 3313 cm-1. The first band is assigned to OH stretching vibrations. The broad bands are ascribed to water stretching vibrations. For sample SAA-090, Raman bands are found at 3063 and 3313 cm-1 with a low intensity broad band at 3193 cm-1. For SAA-072, Raman bands are observed at 3043, 3199 8

and 3333 cm-1. The infrared spectrum of eosphorite in the 2600 to 3800 cm-1 spectral range is reported in Figure 8. The infrared spectrum shows a strong resemblance in spectral profile to the Raman spectrum. A sharp band at 3457 cm-1 with a shoulder at 3440 cm-1 is assigned to the OH stretching vibrations of the hydroxyl units. The two infrared bands at 3065 and 3322 cm-1 are associated with water stretching vibrations. In addition, an infrared band at 3555 cm-1 is observed and is associated with the hydroxyl units.

The Raman spectrum of eosphorite in the 1400 to 2000 cm-1 spectral range is shown in Figure 9. The spectra in this spectral region of the two samples shows differences. Two Raman bands are observed for sample SAA-090 at 1654 and 1748 cm-1. The first band is assigned to the water bending mode. For sample SAA-072, Raman bands are observed at 1573, 1674 and 1724 cm-1. The Raman band at 1674 cm-1 is assigned to water bending modes and the position of the vibration indicates strongly hydrogen bonded water molecules. The infrared spectrum of eosphorite is shown in Figure 10. The infrared band at 1628 cm-1 is attributed to water bending vibrations.

Conclusions We have studied two mineral samples of the phosphate mineral series eosphorite-childrenite

– (Mn,Fe)Al(PO4)(OH)2·(H2O). One sample is manganese rich with a determined formula of

(Mn0.71,Fe0.13,Ca0.01)(Al)1.03(PO4)1.07(OH1.85,F0.02)·2(H2O) and the second is iron rich with a

formula (Fe0.49,Mn0.35,Mg0.06,Ca0.04)(Al)1.03(PO4)1.05(OH)1.80·2(H2O).

The two minerals were analyzed by a combination of Raman and infrared spectroscopy. Raman and infrared bands which are attributed to the phosphate, monohydrogen phosphate, and dihydrogen phosphate units are identified. The determination of the peak areas of the 969, 978 and 1011 cm-1 bands enabled estimates of the ratio of these units to be made. The Mn rich eosphorite showed greater amounts of the phosphate and dihydrogen phosphate units and less of the monohydrogen phosphate; whereas the Fe rich eosphorite contained significantly more of the monophosphate units.

Acknowledgements The financial and infra-structure support of the Discipline of Nanotechnology and Molecular Science, Science and Engineering Faculty of the Queensland University of Technology, is gratefully acknowledged. The Australian Research Council (ARC) is thanked for funding the instrumentation. The authors would like to acknowledge the Center of Microscopy at the Universidade Federal de Minas Gerais (http://www.microscopia.ufmg.br) for providing the equipment and technical support for experiments involving electron microscopy. R. Scholz thanks to FAPEMIG – Fundação de Amparo à Pesquisa do estado de Minas Gerais, (grant No. CRA - APQ-03998-10). C.M. Ferreira thanks PIP/UFOP.

References [1] A.W. Hanson, Acta Crystallographica 13 (1960) 384. [2] H. Berman, F.A. Gonyer, American Mineralogist 15 (1930) 375. [3] T.J. Campbell, W.L. Roberts, Mineralogical Record 17 (1986) 237. [4] J.P. Cassedanne, J.O. Cassedanne, Mineralogical Record 4 (1973) 207. [5] A.M. Fransolet, P. Keller, F. Fontan, Contributions to Mineralogy and Petrology 92 (1986) 502. [6] A.I. Ginzburg, V.V. Matias, Trudy Mineralogicheskogo Muzeya, Akademiya Nauk SSSR 5 (1953) 164. [7] J. Karfunkel, M.L.S.C. Chaves, A. Banko, E. Irran, Mineralogical Record 28 (1997) 489. [8] M.A. Hoyos, T. Calderon, I. Vergara, J. Garcia-Sole, Mineral. Mag. 57 (1993) 329. [9] W.H. Barnes, V.C. Shore, American Mineralogist 36 (1951) 509. [10] A.I. Ginzburg, Trudy Mineralogicheskogo Muzeya, Akademiya Nauk SSSR No. 3 (1951) 133. [11] C.S. Hurlbut, Jr., American Mineralogist 35 (1950) 793. [12] A.C. Pedrosa-Soares, N.C.M. De, C.M. Campos, N.L.C. Da, R.J. Silva, S.M. Medeiros, C. Castañeda, G.N. Queiroga, E. Dantas, I.A. Dussin, F. Alkmim, Geol. Soc. Spec. Pub. 350 (2011) 25. [13] R.L. Frost, W. Martens, P.A. Williams, J.T. Kloprogge, Mineralogical Magazine 66 (2002) 1063. [14] R.L. Frost, W.N. Martens, T. Kloprogge, P.A. Williams, Neues Jahrbuch fuer Mineralogie, Monatshefte (2002) 481. [15] R.L. Frost, P.A. Williams, W. Martens, J.T. Kloprogge, P. Leverett, Journal of Raman Spectroscopy 33 (2002) 260. [16] V.C. Farmer, Mineralogical Society Monograph 4: The Infrared Spectra of Minerals. 1974. [17] C.E. Bamberger, W.R. Busing, G.M. Begun, R.G. Haire, L.C. Ellingboe, Journal of Solid State Chemistry 57 (1985) 248. [18] B.K. Choi, M.N. Lee, J.J. Kim, Journal of Raman Spectroscopy 20 (1989) 11. [19] A. Galy, Journal de Physique et le Radium 12 (1951) 827. [20] H. Poulet, N. Toupry-Krauzman, Proc. Int. Conf. Raman Spectrosc., 6th 2 (1978) 364. [21] N. Toupry-Krauzman, H. Poulet, M. Le Postollec, Journal of Raman Spectroscopy 8 (1979) 115. [22] F.S. Casciani, R.A. Condrate, Sr., Proceedings - International Congress on Phosphorus Compounds 2nd (1980) 175.

List of Tables Table 1. Chemical composition of eosphorite and childrenite from pegmatites from

Minas Gerais. H2O calculated by stoichiometry.

Sample P2O5 Al2O3 MnO FeO CaO MgO H2O F Total SAA-072 34.13 24.05 11.25 16.15 0.89 1.11 15.60 0.02 103.26 SAA-090 34.06 23.68 22.70 4.30 0.13 0.07 15.60 0.13 100.67 Eosphorite* 31.00 22.27 30.99 0.00 0.00 0.00 15.74 0.00 100.00 Childrenite* 30.88 22.18 0.00 31.26 0.00 0.00 15.68 0.00 100.00 P Al Mn Fe Ca Mg H F Mn/(Mn+Fe) SAA-072 1.05 1.03 0.35 0.49 0.04 0.06 3.80 0.00 0.42 6.81 SAA-090 1.07 1.03 0.71 0.13 0.01 0.00 3.85 0.02 0.85 6.81 Eosphorite* 1.00 1.00 1.00 0.00 0.00 0.00 4.00 0.00 7.0 Childrenite* 1.00 1.00 0.00 1.00 0.00 0.00 4.00 0.00 7.0

List of Figures

Figure 1 Raman spectrum of eosphorite over the 100 to 4000 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 2 Infrared spectrum of eosphorite over the 500 to 4000 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 3 Raman spectrum of eosphorite over the 800 to 1400 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 4 Infrared spectrum of eosphorite over the 500 to 1300 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 5 Raman spectrum of eosphorite over the 300 to 800 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 6 Raman spectrum of eosphorite over the 100 to 300 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 7 Raman spectrum of eosphorite over the 2600 to 4000 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 8 Infrared spectrum of eosphorite over the 2600 to 4000 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 9 Raman spectrum of eosphorite over the 1300 to 1800 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 10 Infrared spectrum of eosphorite over the 1300 to 1800 cm-1 spectral range (upper spectrum sample SAA-090, lower spectrum sample SAA-072)

Figure 1 SAA-90 (top) SAA-72 (bottom)

Figure 2 SAA-90 (top) SAA-072 (bottom)

Figure 3 Raman spectrum of SAA-90 (Top), SAA72

Figure 4 SAA-90 (top) SAA-072 (bottom)

Figure 5 Raman spectrum of SAA-90 (top), SAA72

Figure 6 Raman spectrum of SAA-90 (top) , SAA72

Figure 7 Raman spectrum of SAA-90 (top) , SAA72

Figure 8 SAA-90

Figure 9 Raman spectrum of SAA-90 (top) , SAA72

Figure 10 SAA-90 (top) SAA-072 (bottom)