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Journal Article
Published: 01 January 2018
European Journal of Mineralogy (2018) 30 (1): 171-176.
... granite quarry, La Clarté, Perros-Guirec, Ploumanac'h granitic complex, Brittany, France. The empirical formula derived from electron microprobe analysis and single-crystal structure refinement is: A( N a 0.29 K 0.08 ) Σ=0.37 B ( C a 1.69 F e 0.11 2 + M n 0.02 2 + N a 0.18 ) Σ=2.00 C ( F e 1.84 2 + M g...
FIGURES
Journal Article
Published: 01 January 2018
European Journal of Mineralogy (2018) 30 (1): 177-182.
...Edward S. Grew The official International Mineralogical Association (IMA) list of minerals had given the formula for the tinzenite, an axinite-group mineral, as Ca 6 Al 4 [B 2 Si 8 O 30 ](OH) 2 . However, this formula does not correspond to compositions reported for tinzenite, which contain less Ca...
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Journal Article
Journal: Geology
Published: 02 October 2017
Geology (2017) 45 (11): 1007-1010.
...., 1996 , 1995 ). Uranyl minerals affect transport of uranium in the environment, and record the history of natural and anthropogenic processes involving uranium. High-resolution–inductively coupled plasma–mass spectrometry (HR-ICP-MS) was used to determine the empirical formula for ewingite...
FIGURES
Journal Article
Published: 30 June 2017
European Journal of Mineralogy (2017) 29 (6): 1045-1053.
... of sixteen analyses by LA–ICP–MS, H 2 O by TG–DTA, wt%): SiO 2 54.94, Al 2 O 3 0.01, FeO 0.38, MnO 0.80, MgO 0.04, CaO 34.14, Na 2 O 4.37, Li 2 O 2.52 and H 2 O 2.80. The empirical formula of murakamiite, based on 9 O apfu , is (Li 0.55 Na 0.46 ) Σ1.01 (Ca 1.98 Mn 0.04 Fe 0.02 ) Σ2.04 Si 2.98 O 8 (OH) 1.01...
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Journal Article
Published: 26 June 2017
European Journal of Mineralogy (2017) 29 (5): 923-930.
... formula, calculated on the basis of 96 anhydrous oxygen atoms, is (Ba 7.54 K 0.32 Na 0.14 ) Σ8.00 (Ba 3.04 Li 1.57 □ 1.39 ) Σ6.00 Be 24.08 (P 23.88 Al 0.38 Si 0.03 ) Σ24.29 O 96 ·32H 2 O. The single-crystal unit-cell parameters are a = 13.5398(2) Å and V = 2482.21(7) Å, space group I 23. The eight...
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Journal Article
Published: 26 June 2017
European Journal of Mineralogy (2017) 29 (6): 1005-1013.
...). No cleavage was observed. Davidsmithite is hexagonal, space group P 6 3 and has unit-cell dimensions: a = 9.982(1) Å; c = 8.364(2) Å; V = 721.74 Å 3 ; Z =1; the c : a ratio is 0.8379; the calculated density is 2.597 g cm −3 . The approved electron-microprobe analysis gave the crystal–chemical formula: ([Ca...
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Journal Article
Published: 26 June 2017
European Journal of Mineralogy (2017) 29 (6): 1031-1044.
...Cristian Biagioni; Paolo Orlandi Since the beginning of the 2000s, several authors reported the occurrence of As and S as chemical components of the hydrated copper hydroxy-carbonate claraite, originally described with the formula (Cu,Zn) 3 (CO 3 )(OH) 4 ·4H 2 O. Owing to the lack of knowledge...
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Journal Article
Published: 05 April 2017
European Journal of Mineralogy (2017) 29 (5): 907-914.
... = 1.747(3), β = 1.785(3) and γ = 1.808(3) (white light); 2 V = 73(2); dispersion r > v , strong; the optical orientation X = a , Y = b , Z = c . Pleochroism is Y > Z > X in shades of reddish brown. Electron microprobe analyses gave the empirical formula (Ca 3.84 Mn 2+ 0.16 ) Σ4.00 (Mn 3+ 1.33 Al...
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Journal Article
Published: 28 February 2017
European Journal of Mineralogy (2017) 29 (5): 897-905.
...Dan Holtstam; Luca Bindi; Ulf Hålenius; Ulf B. Andersson Delhuyarite-(Ce) is a new mineral (IMA no. 2016-091) with ideal formula Ce 4 Mg(Fe 3+ 2 W)□(Si 2 O 7 ) 2 O 6 (OH) 2 . It is named after Juan and Fausto de Elhuyar (Delhuyar), chemists and metallurgists, who in 1783 isolated tungsten metal...
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Journal Article
Published: 13 February 2017
European Journal of Mineralogy (2017) 29 (5): 915-922.
... formula is 5.93 g/cm 3 . The chemical composition of the mineral (the mean of 10 electron microprobe analyses) is − Na 3.88, Ca 0.29, Pb 72.03, C 4.17, O 19.47 and H 0.17, total 100.00 wt% (H, C and O by stoichiometry assuming the ideal formula). On the basis of 7 O atoms, the empirical formula...
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Journal Article
Published: 01 October 2004
Clays and Clay Minerals (2004) 52 (5): 552-575.
... affected certain horizons resulting in substitution of Al by Fe + Mg while preserving the original layer structure and arrangement. Structural formulae for the berthierine-like phase and berthierine-like layers in these mixed-layer clays show their layer cation composition is intermediate between odinite...
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Journal Article
Published: 01 January 2002
American Mineralogist (2002) 87 (1): 132-141.
... Andranondambo crystals are given in Table 2 . They show that the composition is quite homogeneous, both within a given crystal as well as between different crystals. Using the average compositional data, the crystal-chemical formula calculated on the basis of six oxygen atoms per unit cell can be written...
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Journal Article
Published: 01 January 2002
American Mineralogist (2002) 87 (1): 154-159.
...-crystal neutron diffraction was available. A total of 2.7 g of leucophoenicite powder was obtained from the hand-specimen for neutron diffraction. Electron microprobe analysis gave an average ( n = 10) anhydrous formula [Mn 5.92(12) Mg 0.16(1) Ca 0.64(14) Zn 0.22(2) ] 6.94 Si 3.03(2) O 13 (Table 1...
FIGURES
Journal Article
Published: 01 January 2002
American Mineralogist (2002) 87 (1): 160-170.
..., migmatites, and granulite-facies pegmatite (e.g., Grew 1996 ; Grew et al. 1998 ). McKie (1965) was the first to determine the presently accepted formula, which was confirmed by Stephenson and Moore’s (1968) crystal structure refinement. The first analyses carried out by Pisani ( Lacroix 1903...
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Journal Article
Published: 01 December 2001
The Canadian Mineralogist (2001) 39 (6): 1641-1652.
... formulae, were identified with electron-microprobe data. Compositional variations from Cu 1.80 Pb 1.80 Bi 2.20 S 6 , through Cu 1.53 Pb 1.53 Bi 2.47 S 6 , Cu 1.07 Pb 1.07 Bi 2.93 S 6 , Cu 0.73 Pb 0.73 Bi 3.27 S 6 , to Cu 0.58 Pb 0.58 Bi 3.42 S 6 within a single grain were observed, indicating...
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Journal Article
Published: 01 December 2001
The Canadian Mineralogist (2001) 39 (6): 1653-1663.
... . This difference in coordination gives rise to underbonding of one S site in xilingolite, balanced by an ordered arrangement of Bi 3+ on an adjacent metal site. Electron-microprobe analyses yielded an empirical formula Ag 0.04(0) Pb 2.91(2) Bi 2.07(1) S 5.98(2) . Compared with the simplified formula Pb 3.18 Bi...
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Journal Article
Published: 01 December 2001
The Canadian Mineralogist (2001) 39 (6): 1675-1683.
... 36.31, H 2 O 1.99 (calculated), sum 99.13, yielding the empirical formula (Zn 1.58 Mn 0.31 Mg 0.06 ) ∑1.95 Sb 2.03 [Mg 1.95 Fe 3.88 Al 0.15 ] ∑5.98 O 14.01 (OH) 1.99 . Rinmanite is hexagonal, space group P 6 3 mc , with a 5.9889(4), c 9.353(1) Å, V 290.53(5) Å 3 and Z = 1. A structure refinement from...
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Journal Article
Published: 01 December 2001
The Canadian Mineralogist (2001) 39 (6): 1685-1689.
...). These are canary yellow and transparent, with a vitreous luster and pale yellow streak. It does not fluoresce in ultraviolet radiation. The H Mohs is in the range 2–3. D meas > 4.10 g/cm 3 , D calc = 4.54 g/cm 3 (empirical formula), 4.50 g/cm 3 (idealized formula). Optically biaxial negative, α 1.583(2), β...
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Journal Article
Published: 01 December 2001
The Canadian Mineralogist (2001) 39 (6): 1691-1700.
... rapidly under the electron beam; the crystal-structure determination reveals that there are seven H 2 O groups, giving the ideal formula Mg(V 2 O 6 )·7H 2 O. Dickthomssenite is monoclinic, C 2/ c , a 38.954(2), b 7.2010(4), c 16.3465(9) Å, β 97.602(1)°, V 4544.0(4) Å 3 , Z = 16. The strongest three...
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Journal Article
Published: 01 November 2001
American Mineralogist (2001) 86 (11-12): 1435-1446.
.... Geikielite was analyzed by analytical electron microscopy and has the formula Mg 0.83 Fe 0.15 Mn 0.02 (Ti 0.99 Fe 0.01 )O 3 . The textural relationships between geikielite inclusions and spinel matrix, combined with the analytical data, suggest that geikielite laths represent exsolution features, thus...
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