... granitic pegmatite, Sahatany Valley, Madagascar. Boralsilite also occurs in this association, although separately from vránaite; both minerals form rare aggregates of subparallel prisms up to 100 μm long. Optically, vránaite is biaxial (−), n α = 1.607(1), n β = 1.634(1), n γ = 1.637(1) (white light), 2 V...

... pegmatite, Sahatany Valley, Madagascar. The pegmatite mineral assemblage is relatively simple (Ab + Qz > Kfs > Tur + Spd > Ap + several accessory B-rich phases). This pegmatite forms an E–W-trending elongated body emplaced in an Mg-rich calc-silicate rock; the pegmatite exocontact locally contains...

...Andreas Ertl; Ekkehart Tillmanns; Theodoros Ntaflos; Carl Francis; Gerald Giester; Wilfried Körner; John M. Hughes; Christian Lengauer; Markus Prem Abstract An Al-rich tourmaline from the Sahatany Pegmatite Field at Manjaka, Sahatany Valley, Madagascar, was structurally and chemically...

... Brl, Cs-rich Phl etc . in a narrow exocontact zone between elbaite-subtype pegmatite with common spodumene and calc-silicate rock at Manjaka, Sahatany Valley, Madagascar ( Novák et al . 2015 ). Concentrations of Ti in the examined tourmalines reach up to 4.11, 4.69, and 4.70 wt.% TiO 2...

... of Be or Li. As far as we have been able to determine, this was the last published composition of Russian rhodizite. Subsequently, rhodizite was found in several locations in Madagascar ( Fig. 1 ) including Antandrokomby near Mt. Ibity and at Manjaka in the Sahatany valley ( Lacroix 1922 ). Results...

...., & Krivovichev, S.V. (2016) Vránaite, ideally Al 16 B 4 Si 4 O 38 , a new mineral related to boralsilite, Al 16 B 6 Si 2 O 37 , from the Manjaka pegmatite, Sahatany Valley, Madagascar . American Mineralogist 101 (9) , 2108 – 2117...

... ) discovery in fluid inclusions . Petrology , 8 , 214 – 237 . Ranorosoa , N. , Fontan , F. , and Fransolet , A-M. ( 1989 ) Rediscovery of manandonite in the Sahatany valley, Madagascar . European Journal of Mineralogy , 1 , 633 – 638 . Rijks , H.R.P. and van der Veen...

... described by Lussier et al. (2008 , 2009 ). An Al-rich tourmaline with unit-cell parameters a =  15.777(1), c =  7.086(1) Å from the Sahatany Pegmatite Field at Manjaka, Sahatany Valley, Madagascar, contains also a significant amount of [4] B (∼0.4 apfu, no [4] Al; 〈 T –O〉 = 1.611(1) Å; Ertl et...

.... , Groat , L.A. , Krivovichev , S.V. ( 2016 ): Vránaite, ideally Al 16 B 4 Si 4 O 38 , a new mineral related to boralsilite, Al 16 B 6 Si 2 O 37 , from the Manjaka pegmatite, Sahatany Valley, Madagascar . Am. Mineral. , 101 , 2108 – 2117 . Chaisson , E.J. ( 2001 ): Cosmic...

... in the Antandrokomby pegmatite (latitude 20°11′45″ S; longitude 47°0′19″ E; elevation 1300 m above sea level), near Mt. Ibity, in the southern part of the Sahatany Pegmatite Field, Manandona Valley, Vakinankaratra region, Antananarivo Province, Madagascar. The Antandrokomby pegmatite belongs to a tectonic unit known...

... 2 O) 5.90, BeO 10.10, Al 2 O 3 30.50, B 2 O 3 40.60, SiO 2 1.36, LOI 0.45, total 99.51 wt.% ( Lacroix 1910 ). Duparc et al. (1911) analyzed rhodizite from the Manjaka pegmatite, Sahatany valley, Betafo Department, Madagascar, and obtained the following data: Li 2 O 0.68, Na 2 O 1.78, K 2 O...

.... and Baijot, M. (2016) Mengxianminite, IMA 2015-070. CNMNC Newsletter No. 29, February 2016, page 200; Mineralogical Magazine , 80 , 199–205. Al 16 B 4 Si 4 O 38 Manjaka pegmatite, Sahatany Valley pegmatite field, 25 km SW of Antsirabe, Itremo Region, Madagascar (20°04′35″S, 46°57′09″E) Jan...

... (H 2 O) Antandrokomby pegmatite, near Mt. Ibity, Sahatany Pegmatite Field, Manandona Valley, Vakinankaratra Region, Antananarivo Province, Madagascar (20°14′25″S, 47°1′19″E) Cristian Biagioni*, Reto Gieré, Nicolas Meisser, Fabrizio Nestola, Marco Pasero, Martin Robyr, Philippe Roth and Cédric...

...) Antandrokomby pegmatite, near Mt. Ibity, Sahatany Pegmatite Field, Manandona Valley, Vakinankaratra Region, Antananarivo Province, Madagascar (20°14′25″S, 47°1′19″E) Cristian Biagioni*, Reto Gieré, Nicolas Meisser, Fabrizio Nestola, Marco Pasero, Martin Robyr, Philippe Roth and Cédric Schnyder *E...

.... The pegmatite is located near Mt. Ibity, in the southern part of the Sahatany Pegmatite Field, Manandona Valley, Vakinankaratra region, Antananarivo Province, Madagascar (20°11′45″ S; 47°0′19″ E). Hydrokenopyrochlore occurs as relics, closely associated with quartz, orthoclase, Li-rich mica, hübnerite...

...Figure 2. Raman spectroscopy applied to determine the chemical composition of members of the tourmaline group, and for their assignment to a mineral species. ( A ) A fluorliddicoatite and a fluor-elbaite specimen, both originating from the Tsarafara pegmatite, Sahatany Valley (Madagascar). P...