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American Mineralogist, Volume 86, pages 1534–1537, 2001 NEW MINERAL NAMES* JOHN L. JAMBOR1 AND ANDREW C. ROBERTS2 1Department of Earth and Ocean Sciences, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada 2Geological Survey of Canada, 601 Booth Street, Ottawa K1A 0E8, Canada 3 DASHKOVAITE* (93.4–132), Dmeas = 3.15–3.20, Dcalc = 3.23 g/cm for Z = 2. α β γ N.V. Chukanov, D.I. Belakovsky, S.V. Malinko, N.I. Organova Optically biaxial negative, = 1.596, = = 1.648, 2Vmeas = ~0º, 2Vcalc = 0º, Y = b; strongly pleochroic, X = pale brown, Y = (2000) Dashkovaite Mg(HCO3)2·2H2O — A new formate mineral. Zapiski Vseross. Mineral. Obshch., 129(6), 49–53 dark green, Z = reddish brown. Electron microprobe and wet- (in Russian, English abs.). chemical analyses gave K2O 8.73, Na2O 0.19, Rb2O 0.42, CaO 0.02, BaO 0.44, SrO 0.01, FeO 26.19, Fe2O3 7.86 (Fe parti- Chemical analysis gave C 16.2, H 3.9, Mg 16.4, Mn (by tioned by Mössbauer spectroscopy), MgO 1.49, MnO 0.68, Li2O electron microprobe) 0.2, O (by difference) 63.3, sum 100 wt%, 0.47, TiO2 1.29, ZnO 0.27, NiO 0.01, SiO2 34.12, Al2O3 13.89, corresponding to Mg1.00Mn0.01H5.74C2.00O5.87, ideally Mg(HCO3)2 H2O 0.91, F 3.91, O ≡ F 1.65, sum 99.25 wt%, corresponding 2+ 3 + · 2H2O. The mineral occurs as white, fibrous aggregates in hy- to (K0.92Na0.03Rb0.02Ba0.01)Σ0.98(Fe1 .82Fe0 .49Al0.19Mg0.18Li0.16 drothermal veinlets, up to 1 mm in width, wherein the fibers Ti0.08Mn0.05Zn0.02)Σ2.99(Si2.83Al1.17)Σ4.00(F1.03OH0.50■0.47)Σ2.00, simpli- 2+ are up to 3 mm long and 0.01 mm wide. Soft and porous, H = fied as KFe3 AlSi3O10F2, which is the F analog of annite. Single- 3 1, Dcalc = 1.74 g/cm for Z = 4. Microscopically colorless, bi- crystal X-ray structure study indicated monoclinic symmetry, axial positive, α = 1.465(3), β = 1.486(3), γ = 1.516(3), 2Vcalc = space group C2/m, 1M polytype, a = 5.369(8), b = 9.289(3), c 81(5)°, X parallel to the elongation. By analogy with the syn- = 10.153(8) Å, β = 100.49(1)°. Strongest lines of the powder thetic analog, indexing of the X-ray powder pattern gave a pattern (diffractometer, CuKα radiation) are 10.09(100,001), monoclinic cell, space group P21/c, a = 8.64(1), b = 7.15(1), c 5.02(13,002), 3.336(56,003), and 2.507(14,131,004). = 9.38(1) Å, β = 98.0(1)°; strongest lines of the pattern (57 mm The mineral is a rock-forming species in the upper part of – camera, FeKα radiation) are 4.90(90,111), 4.64(80,002), an A-type granite at Suzhou, near Shanghai, eastern China. Type 4.30(70,200), 3.68(80,210), and 3.40(100,112). The IR spec- material is in the Geology and Mineral Resources Institute in trum is similar to that of the synthetic compound. Chengdu, and in the Geological Museum of China, at Beijing. The mineral occurs with shabynite, iowaite, ekaterinite, J.L.J. korshunovskite, halite, hydromagnesite, and serpentine in do- lomite marble at the Korshunovskoye boron deposit in the FLUORO-MAGNESIO-ARFVEDSONITE* Irkutsk district, Siberia. The new mineral name is for E.R. A.G. Bazhenov, I.L. Nedosekova, T.V. Krinova, A.B. Dashkova (1744–1810), former Director of the Saint Peters- Mironov, P.V. Kvorov (2000) Fluormagnesioarfvedsonite 2+ 3+ burg Academy of Sciences (1783–1796) and President of the NaNa2(Mg,Fe )4Fe [Si8O22](F,OH)2 — A new mineral species Russian Academy of Sciences. Type material is in the Fersman of the amphibole group (Ilmen-Vishnevye Mountains alkaline Mineralogical Museum, Moscow, Russia. J.L.J. massif, south Urals). Zapiski Vseross. Mineral. Obshch., 129(6), 28–35 (in Russian, English abs.). FLUORANNITE* Ganfu Shen, Qi Lu, Jinsha Xu (2000) Fluorannite: A new The mineral occurs as light gray, short prismatic grains in mineral of the mica group from the western suburb of Suzhou albite-microcline fenite in the contact zone of the Ilmen alka- City. Acta Petrologica Mineral., 19(4), 355–362 (in Chinese, line massif. Wet-chemical analysis gave SiO2 56.76 TiO2 0.51, English abs.). Al2O3 1.47, Fe2O3 5.76, FeO 0.79, MnO 0.29, MgO 20.10, CaO + 2.86, Na2O 7.50, K2O 1.62, H2O 0.84, F 2.80, O ≡ F 1.18, sum The mineral occurs as euhedral to subhedral sheets and tabu- 100.12 wt%, corresponding to (Na0.44K0.29)Σ0.73(Na1.57Ca0.43)Σ2.00 2+ 3+ lar crystals to more than 6 mm across, but predominantly 2–4 (Mg4.14Mn0.03Fe0 .09Fe0 .60Ti0.05Al0.09)Σ5.00[(Si7.85Al0.15)Σ8.00O22] mm long and 1–3 mm wide. Iron-black color, submetallic lus- (F1.22OH0.78)Σ2.00, which is the F analog of magnesio-arfvedsonite. 1 ter, perfect {001} cleavage, sectile, gray streak, VHN = 109 Brittle, H = 5 /2, {110} cleavage, Dmeas= 3.09, Dcalc = 3.04 g/ cm3 for Z = 2. Optically biaxial positive, α = 1.618, β = 1.629, γ = 1.632, 2Vmeas = 50–70°, c:Z = 15–16°, optic-axis plane (010), *Before publication, minerals marked with an asterisk were pleochroism X = yellowish, almost colorless, Y = lilac, Z = approved by the Commission on New Minerals and Mineral greenish blue, Z > Y > X. Indexing of the X-ray powder Names, International Mineralogical Association. diffractogram (FeKα radiation) gave a monoclinic cell with a 0003-004X/01/1112–1534$05.00 1534 JAMBOR AND ROBERTS: NEW MINERAL NAMES 1535 = 9.81(9), b = 18.01(3), c = 5.28(1) Å, β = 103.8(2)°, probable material, charge balance is not possible for (Y,REE) > Ca and space group C2/m. Strongest lines are 8.42(34,110), B <4; that is, the only charge-balanced, alkali-free end-mem- 3.264(23,240), 3.129(100,310), 2.804(28,330), and ber for a Y analog of hyalotekite is Ba4(YCa)[Si8B4O28F]. J.L.J. 2.708(17,151). The mineral is associated with perthite, microcline, albite, KRETTNICHITE* phlogopite, quartz, and accessory titanite, rutile, apatite, py- J. Brugger, T. Armbruster, A. Criddle, P. Berlepsch, S. Graeser, rite, and zircon. Type material is in the Natural Science Mu- S. Reeves (2001) Description, crystal structure, and paragen- 3+ 3+ seum of the Ilmen State Preserve at Miass, and in the esis of krettnichite, PbMn2 (VO4)2(OH)2, the Mn analogue Mineralogy Department of the Saint Petersburg Mining Insti- of mounanaite. Eur. J. Mineral., 13, 145–158. tute, Russia. Discussion. Although it is written as “fluormagnesioarfvedsonite” The mineral occurs as radiating aggregates, to 3 cm diam- in both the English abstract and the Russian version of the pub- eter, of dark brown platy (001) crystals, as <1 mm acicular to lication, the new mineral name should be fluoro-magnesio- prismatic black crystals, and as brownish pseudorhombohedral arfvedsonite to conform to the CNMMN-approved crystals showing {001}, {111}, {332}, and {331}. Adaman- 1 nomenclature system for the amphiboles. J.L.J. tine luster, brown streak, H = 4 /2, excellent {001} cleavage and a distinct one at a high angle to it, nonfluorescent, Dmeas = KAPITSAITE-(Y)* 3 >4.04, Dcalc = 4.51–4.81 g/cm for Z = 2. Electron microprobe L.A. Pautov, P.V. Khvorov, E.V. Sokolova, G. Ferraris, G. Ivaldi, analysis gave CaO 0.60, BaO 0.90, SrO 1.48, PbO 32.66, CuO L.F. Bazhenova (2000) Kapitsaite-(Y) (Ba,K)4 0.42, CoO 2.22, NiO 0.04, Al2O3 0.04, Fe2O3 1.25, Mn2O3 24.03, (Y,Ca)2Si8(B,Si)4O28F — A new mineral. Zapiski Vseross. As2O5 2.92, V2O5 29.26, H2O (calc.) 3.54, sum 99.43 wt%, cor- 3+ Mineral. Obshch., 129(6), 42–49 (in Russian, English abs.). responding to (Pb0.83Sr0.08Ca0.06Ba0.03)Σ1.00 (Mn1 .73Co0.17Fe0.09 Cu0.03Al0.01)?2.03(V1.83As0.14)Σ1.97O7.71(OH)2.23, ideally PbMn2(VO4)2(OH)2. The mineral occurs as a pale pink, sheaf-like aggregate, 1 × In transmitted light, only thin (001) plates are transparent. Red- 3 cm. The average of seven listed electron microprobe analy- dish brown color, distinct pleochroism towards orange; ncalc from ses (REE titrometrically, B colorimetrically, and Be by atomic reflectance measurements at 590 nm are 2.21 for R1 and 2.39 absorption) is SiO2 34.98, Al2O3 0.04, FeO 0.01, MnO 0.05, for R2. Single-crystal X-ray structure study gave monoclinic CaO 3.12, K2O 0.87, Na2O 0.46, PbO 1.95, BaO 38.18, Y2O3 symmetry, space group C2/m; a = 9.275(7), b = 6.284(3), c = 7.93, La2O3 0.01, Ce2O3 0.09, Pr2O3 0.03, Nd2O3 0.32, Sm2O3 7.682(2) Å, β = 117.97(4)° as refined from a diffractometer 0.36, Gd O 0.64, Dy O 0.70, Ho O 0.14, Er O 0.36, Yb O powder pattern (CuKα radiation) with strongest lines of 2 3 2 3 2 3 2 3 2 3 – 0.20, B2O3 8.68, BeO <0.02, F 1.40, Cl 0.01, O ≡ F 0.59, sum 3.388(95,002), 3.270(100, 112), 2.946(51,201), 2.850(49,021), 99.94 wt%, corresponding to (Ba3.54K0.26Pb0.12Na0.07)Σ3.99 2.4910(93,112,220), and 1.6962(83,004).
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    PRE-TREATMENT OF TANTALUM AND NIOBIUM ORES FROM DEMOCRATIC REPUBLIC OF CONGO (DRC) TO REMOVE URANIUM AND THORIUM Elie KABENDE BSc (Applied Physics) GradDip (Extractive Metallurgy) 2020 This thesis is presented for the degree of Masters of Philosophy at Murdoch University DECLARATION I declare that this thesis is my own account of my research contains as its main content work which has not previously been submitted for a degree at my tertiary education institution. E …………………………………………. Elie kabende ABSTRACT Tantalum (Ta) and niobium (Nb) have applications in high-technology electronic devices and steel manufacturing, respectively. Africa, South America and Australia collectively provide about 80% of the global supply of Ta-Nb concentrates. In Africa, Sociéte Minière de Bisunzu (SMB) located in the Democratic Republic of Congo (DRC) remains the major supplier of Ta- Nb concentrates containing about 33 wt % Ta2O5 and 5 wt % Nb2O5 as the two oxides of main economic values, associated with uranium (0.14 wt %) and thorium (0.02 wt %). The presence of U and Th complicates the transportation logistics of tantalite to international markets, due to stringent regulation on an allowable limit of U and Th at 0.1 wt %. High radiation levels also hinder further primary beneficiation of the Ta-Nb concentrates at the Bisunzu mine to an extent of at least 50 wt % Ta2O5 and Nb2O5 combined. Digestion of the concentrate using HF is the conventional method to remove U and Th followed by chemical treatment to recover Ta2O5 and Nb2O5. The HF digestion process is hazardous and requires large investments. The main objective of this study is the mineral identification in the ore and concentrates of SMB mine sites, to investigate the possibilities of upgrading the Ta2O5 and the Nb2O5 by weight using physical separation and concentration, and removing U and Th using chemical treatment.
  • Lecture Notes - Mineralogy - Periclase Structure

    Lecture Notes - Mineralogy - Periclase Structure

    Lecture Notes - Mineralogy - Periclase Structure • In lab we determined the unit cell for a crystal of synthetic periclase (MgO). Because periclase is cubic, only one lattice parameter (a) is needed to completely specify the size and shape of the unit cell. We found that a = 0.421 nm (= 4.21 Å). Based on this measurement, the volume (V) of the periclase unit cell is 0.074618 nm3. • The density of periclase can be determined by a specific gravity measurement using either the Joly or Berman balance. Because periclase is very hygroscopic, the Berman balance with tolu- ene as the fluid is to be recommended. Periclase has a density of 3.56 g/cm3 (=3.56 x 10-21 g/ nm3). One unit cell contains 2.6564 x 10-22 gm of periclase. [(0.074618 nm3/unit cell) x (3.56 x 10-21 gm of periclase/nm3) = (2.6564 x 10-22 gm of periclase/unit cell)] • One gram formula unit (mole) of periclase has a mass (gfw) of 40.31 gms and contains N (6.023 x 1023) formula units of MgO. Therefore, there are [(6.023 x 1023 formula units of MgO)/(40.31 gms) =] 1.494 x 1022 formula units of periclase per gram of periclase. • Using the results of (2) and (3) it is clear that there should be [(1.494 x 1022 formula units of periclase/gm of periclase) x (2.6564 x 10-22 gm of periclase/unit cell) =] 3.969 formula units of periclase/unit cell. This number Z (formula units/unit cell) must be an integer (Z = 4) because there cannot be fractions of atoms in the unit cell.
  • Radiocarbon Dating of Anthropogenic Carbonates: What Is the Benchmark for Sample Selection?

    Radiocarbon Dating of Anthropogenic Carbonates: What Is the Benchmark for Sample Selection?

    heritage Review Radiocarbon Dating of Anthropogenic Carbonates: What Is the Benchmark for Sample Selection? Michael B. Toffolo Institut de Recherche sur les Archéomatériaux-Centre de Recherche en Physique Appliquée à l’Archéologie (IRAMAT-CRP2A), UMR 5060 CNRS, Université Bordeaux Montaigne, 8 Esplanade des Antilles, 33607 Pessac, France; michael.toff[email protected] Received: 6 November 2020; Accepted: 21 November 2020; Published: 24 November 2020 Abstract: Anthropogenic carbonates are pyrotechnological products composed of calcium carbonate, and include wood ash, lime plaster/mortar, and hydraulic mortar. These synthetic materials are among the first produced by humans, and greatly influenced their biological and cultural evolution. Therefore, they are an important component of the archeological record that can provide invaluable information about past lifeways. One major aspect that has been long investigated is the possibility of obtaining accurate radiocarbon dates from the pyrogenic calcium carbonate that makes up most of these materials. This is based on the fact that anthropogenic carbonates incorporate atmospheric carbon dioxide upon the carbonation of hydrated lime, and thus bear the radiocarbon signature of the atmosphere at a given point in time. Since plaster, mortar, and ash are highly heterogeneous materials comprising several carbon contaminants, and considering that calcium carbonate is prone to dissolution and recrystallization, accurate dating depends on the effectiveness of protocols aimed at removing contaminants and on the ability to correctly identify a mineral fraction that survived unaltered through time. This article reviews the formation and dissolution processes of pyrogenic calcium carbonate, and mineralogical approaches to the definition of a ‘dateable fraction’ based on its structural properties.