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magnesiodumortierite

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Journal Article
Published: 01 May 2018
European Journal of Mineralogy (2018) 30 (3): 471–483.
...-dumortierite, magnesiodumortierite from the Dora-Maira Massif, which is assumed to have formed at similar conditions (2.5–3.0 GPa, 700 °C), does not show any B-excess. Tourmaline shows an analogous behaviour in that magnesium-rich ( e.g ., dravitic) tourmaline formed at high pressure shows no or only minor...
FIGURES
First thumbnail for: Synthetic [4] B-bearing dumortierite and natural [...
Second thumbnail for: Synthetic [4] B-bearing dumortierite and natural [...
Third thumbnail for: Synthetic [4] B-bearing dumortierite and natural [...
Journal Article
Published: 01 June 1995
European Journal of Mineralogy (1995) 7 (3): 525–535.
Journal Article
Published: 01 February 1995
European Journal of Mineralogy (1995) 7 (1): 167–174.
Image
Photomicrograph (plane-polarized light) of coexisting magnesiodumortierite (Mg–du) and ellenbergerite (el) inclusions in pyrope (py) from the Dora-Maira Massif, Western Alps, Italy (sample DM-du II). Further abbreviation: rt = rutile; ky = kyanite; chl = chlorite.
Published: 01 May 2018
Fig. 2 Photomicrograph (plane-polarized light) of coexisting magnesiodumortierite (Mg–du) and ellenbergerite (el) inclusions in pyrope (py) from the Dora-Maira Massif, Western Alps, Italy (sample DM-du II). Further abbreviation: rt = rutile; ky = kyanite; chl = chlorite.
Image
Octahedral cation contents in the fibers from rose quartz (this study), classic dumortierite (Alexander et al. 1986), and magnesiodumortierite (Chopin et al. 1995).
Published: 01 February 2002
F igure 8. Octahedral cation contents in the fibers from rose quartz (this study), classic dumortierite ( Alexander et al. 1986 ), and magnesiodumortierite ( Chopin et al. 1995 ).
Journal Article
Published: 01 August 2013
Mineralogical Magazine (2013) 77 (6): 2825–2839.
... occupancy of the Al1 site is critical. (1) Dumortierite group, with Al1 = Al 3+ , Mg 2+ and □, where □ denotes cation vacancy. Charge balance is provided by OH substitution for O at the O2, O7 and O10 sites. In addition to dumortierite, endmember composition AlAl 6 BSi 3 O 18 , and magnesiodumortierite...
FIGURES
First thumbnail for: The dumortierite supergroup. I. A new nomenclature...
Second thumbnail for: The dumortierite supergroup. I. A new nomenclature...
Third thumbnail for: The dumortierite supergroup. I. A new nomenclature...
Journal Article
Published: 01 May 2000
European Journal of Mineralogy (2000) 12 (3): 521–528.
... and electron-microprobe analysis in order to elucidate the origin of colour and pleochroism: (a) deep blue dumortierite from Sahatany, Madagascar, (b) red magnesiodumortierite from Dora-Maira, Western Alps, and (c) deep violet dumortierite from Arizona, USA. The Fe and Ti contents are, respectively, 0.020...
FIGURES
First thumbnail for: Fe 2+ -Ti 4+ charge-transfer in dumortierite
Second thumbnail for: Fe 2+ -Ti 4+ charge-transfer in dumortierite
Third thumbnail for: Fe 2+ -Ti 4+ charge-transfer in dumortierite
Journal Article
Published: 01 October 2012
The Canadian Mineralogist (2012) 50 (5): 1197–1231.
.... Smaller triangular channels contain planar BO 3 groups, while in other materials the triangular channels are occupied by tetrahedral or pyramidal groups. Holtite and magnesiodumortierite are isostructural with dumortierite, while ellenbergerite, phosphoellenbergerite, ekatite, and the synthetic materials...
FIGURES
First thumbnail for: STRUCTURE AND TOPOLOGY OF DUMORTIERITE AND DUMORTI...
Second thumbnail for: STRUCTURE AND TOPOLOGY OF DUMORTIERITE AND DUMORTI...
Third thumbnail for: STRUCTURE AND TOPOLOGY OF DUMORTIERITE AND DUMORTI...
Journal Article
Published: 01 August 2003
Mineralogical Magazine (2003) 67 (4): 799–806.
... grades ( Schreyer et al. , 1975 ; Takahata and Uchiyama, 1985 ; Beukes et al. , 1987 ; Chopin et al. , 1995 ). The dumortierite group consists of two types of minerals, namely, dumortierite and magnesiodumortierite. The transition from dumortierite to Ti-free magnesiodumortierite is favoured...
FIGURES
First thumbnail for: Textural and spectroscopic studies on hydrothermal...
Second thumbnail for: Textural and spectroscopic studies on hydrothermal...
Third thumbnail for: Textural and spectroscopic studies on hydrothermal...
Image
Unit-cell parameters b versus a (space group Pmcn) for dumortierite group minerals. The black circles represent naturally-occurring dumortierite [4 unpublished data, 12 from Alexander et al. (1986), 4 from Groat et al. (2012), 2 from Fuchs et al. (2005), 2 from Evans et al. (2012), and one each from Moore & Araki (1978b), Beukes et al. (1987), Taner & Martin (1993), Choo & Kim (2001), Cempírek & Novák (2005), and Mahapatra & Chakrabarty (2011)]; white circles, synthetic dumortierite [21 from Werding & Schreyer (1990)]; black squares, holtite [one unpublished datum, 4 from Groat et al. (2009), and one each from Pryce (1971), Hoskins et al. (1989), Kazantsev et al. (2006), and Zubkova et al. (2006)]; the black star represents magnesiodumortierite [from Ferraris et al. [1995)]; the dashed line is b=3a.
Published: 01 October 2012
squares, holtite [one unpublished datum, 4 from Groat et al . (2009) , and one each from Pryce (1971) , Hoskins et al . (1989) , Kazantsev et al . (2006) , and Zubkova et al . (2006) ]; the black star represents magnesiodumortierite [from Ferraris et al . [1995) ]; the dashed line is b
Journal Article
Published: 01 February 2012
American Mineralogist (2012) 97 (2-3): 329–340.
... of the important crystal-chemical substitutions in the dumortierite group minerals occur in the hexagonal channels, for example (Ta 5+ , Nb 5+ ) at Al1 and (As 3+ , Sb 3+ ) at Si1 and Si2 in holtite (see below), (Mg 2+ , Ti 4+ ) at Al1 in magnesiodumortierite, and significant vacancies at Al1 in all three minerals...
FIGURES
First thumbnail for: MAS NMR measurements and ab initio calculations of...
Second thumbnail for: MAS NMR measurements and ab initio calculations of...
Third thumbnail for: MAS NMR measurements and ab initio calculations of...
Journal Article
Published: 01 February 2002
American Mineralogist (2002) 87 (2-3): 269–276.
...F igure 8. Octahedral cation contents in the fibers from rose quartz (this study), classic dumortierite ( Alexander et al. 1986 ), and magnesiodumortierite ( Chopin et al. 1995 ). ...
FIGURES
First thumbnail for: Fibrous nanoinclusions in massive rose quartz: HRT...
Second thumbnail for: Fibrous nanoinclusions in massive rose quartz: HRT...
Third thumbnail for: Fibrous nanoinclusions in massive rose quartz: HRT...
Journal Article
Published: 01 February 2012
Jour. Geol. Soc. India (2012) 79 (2): 181–188.
..., 1996 ). The dumortierite group consists of two types of minerals, namely, dumortierite and magnesiodumortierite. The transition from dumortierite to Ti-free magnesiodumortierite is favoured by increasing pressure ( Chopin et al. 1995 ). The ionic potentials of elements such as Fe, Ti and Mn...
FIGURES
First thumbnail for: Mineralogy and Origin of Dumortierite from Girola ...
Second thumbnail for: Mineralogy and Origin of Dumortierite from Girola ...
Third thumbnail for: Mineralogy and Origin of Dumortierite from Girola ...
Journal Article
Published: 01 January 2005
European Journal of Mineralogy (2005) 17 (1): 173–183.
...% for dumortierite from Weißenkirchen in der Wachau ( Table 3 ). Similar MgO contents have been found in dumortierite samples from the Saxonian Erzgebirge, Germany (Groat et al. , in prep.). Magnesiodumortierite (a “high-pressure mineral”) from the Dora Maira Massif, Western Alps, contains up to ∼ 5.8–8.7 wt% MgO...
FIGURES
First thumbnail for: Dumortierite from the Gföhl unit, Lower Austria :...
Second thumbnail for: Dumortierite from the Gföhl unit, Lower Austria :...
Third thumbnail for: Dumortierite from the Gföhl unit, Lower Austria :...
Journal Article
Published: 01 August 2013
Mineralogical Magazine (2013) 77 (6): 2841–2856.
... constituting the supergroup: dumortierite, endmember (Al)Al 6 BSi 3 O 18 , magnesiodumortierite, endmember (Mg)Al 6 BSi 3 O 17 (OH), and holtite, endmember (Ta 0.6 □ 0.4 )Al 6 B 3 Si 3 O 18 ( Pieczka et al. , 2013 ). Here we describe three new minerals in the dumortierite supergroup from the Szklary...
FIGURES
First thumbnail for: The dumortierite supergroup. II. Three new mineral...
Second thumbnail for: The dumortierite supergroup. II. Three new mineral...
Third thumbnail for: The dumortierite supergroup. II. Three new mineral...
Journal Article
Published: 01 May 2018
European Journal of Mineralogy (2018) 30 (3): 411–412.
.... , Schertl , H.-P. , Chopin , C. ( 2018 ): Synthetic [4] B-bearing dumortierite and natural [4] B-free magnesiodumortierite from the Dora-Maira Massif: Differences in boron coordination in response to ultrahigh pressure . Eur. J. Mineral. , 30 , DOI: 10.1127/ejm/2018/0030-2742...
Journal Article
Published: 01 July 2001
European Journal of Mineralogy (2001) 13 (4): 769–777.
... of the face-sharing octahedra are ordered with one Mg and one Al in each dimer ( Fig. 5b ). The consequence is a change in symmetry from space group P 6 3 mc to P 6 3 . The structure comparison of ellenbergerite with magnesiodumortierite, idealized as (Mg,Ti, □)(Al, □) 4 (Al,Mg,□) 2 (OH) 3 (BO 3 )[(Si...
FIGURES
First thumbnail for: Ekatite, (Fe 3+ , Fe 2+ , Zn) 12 (OH) 6 [AsO 3 ] 6...
Second thumbnail for: Ekatite, (Fe 3+ , Fe 2+ , Zn) 12 (OH) 6 [AsO 3 ] 6...
Third thumbnail for: Ekatite, (Fe 3+ , Fe 2+ , Zn) 12 (OH) 6 [AsO 3 ] 6...
Image
Unit-cell parameters a versus c for DLMs. Sources for naturally occurring dumortierite (black circles), synthetic dumortierite (white circles), holtite (black squares), and magnesiodumortierite (black star) are given in the caption to Fig. 5. Black triangles represent ellenbergerite [2 data from Comodi & Zanazzi (1993a), one each from Chopin et al. (1986), Comodi & Zanazzi (1993b), and Zubkova et al. (2007)]; black inverted triangles, natural phosphoellenbergerite [from Raade et al. (1998)]; white inverted triangles, synthetic phosphoellenbergerite [4 data from Brunet et al. (1998)]; black diamonds, ekatite [from Keller (2001)]; white hexagons, TM phosphites [2 data from Marcos et al. (1993b), 2 from Attfield et al. (1994), 2 from Ni et al. (2009), and one each from Marcos et al. (1993c), Che et al. (2005), Gu et al. (2007), and Liao & Ni (2010)]; white crosses, metal pnictates [3 data from Marcos et al. (1993a), 2 from Marcos et al. (1995), 2 from Hughes et al. (2003), and 2 from Rojo et al. (2002)]; white squares, TM chalcogenites [4 data from Amorós et al. (1996), 2 from Perez et al. (1976), and one from Marcos et al. (1993a)]; white diamonds, metal vanadates and sulfate-vanadates [one each from Kato et al. (1998), Zhang et al. (1999), Đođević et al. (2008), and Hu et al. (2008)]; the dashed line is the calculated b/a ratio (equation 6). Error bars on each point are smaller than the symbols.
Published: 01 October 2012
Fig. 8 Unit-cell parameters a versus c for DLMs. Sources for naturally occurring dumortierite (black circles), synthetic dumortierite (white circles), holtite (black squares), and magnesiodumortierite (black star) are given in the caption to Fig. 5 . Black triangles represent ellenbergerite [2
Journal Article
Published: 01 August 2012
The Canadian Mineralogist (2012) 50 (4): 855–872.
... in granitic pegmatites compared to tourmaline, dumortierite is a typical mineral of the abyssal class, AB-BBe subclass of pegmatites, which Černý & Ercit (2005) recognized in their revision of the classification of pegmatites. Magnesiodumortierite [ ca. (Mg,Ti,□)Al 4 (Al,Mg) 2 (BO 3 )Si 3 O 12 (OH,O) 3...
FIGURES
First thumbnail for: The Crystal Chemistry of As- and Sb-bearing Dumort...
Second thumbnail for: The Crystal Chemistry of As- and Sb-bearing Dumort...
Third thumbnail for: The Crystal Chemistry of As- and Sb-bearing Dumort...
Journal Article
Journal: Elements
Published: 01 August 2013
Elements (2013) 9 (4): 261–266.
... is stable at much lower pressures (P > 0.5 GPa) and higher temperatures (T < 1000 °C; Brunet et al. 1998 ). Magnesiodumortierite ( T able 2 )—like ellenbergerite, with chains of face-sharing octahedra—was also described as a new species from the Dora-Maira massif. It forms inclusions in pyrope...
FIGURES
First thumbnail for: Continental Crust at Mantle Depths: Key Minerals a...
Second thumbnail for: Continental Crust at Mantle Depths: Key Minerals a...
Third thumbnail for: Continental Crust at Mantle Depths: Key Minerals a...