...Charles Milton; Blanche Ingram; Irving Breger Abstract Fibrous authigenic sodic amphibole (similar to magnesioarfvedsonite in composition) from the Green River Formation of Utah has been analyzed, the first analysis of a diageneticam phibole to be reported. Intim ate intergrowth of the fibers...

...-perthite, nepheline and manganoeudialyte crystals cemented by fine-acicular aegirine. Minor rock-forming minerals include sodalite, natrolite, magnesioarfvedsonite, and selivanovaite (up to 10 modal %). Characteristic accessory minerals are lamprophyllite, murmanite, loparite-(Ce), a pyrochlore-group...

..., zoned diopside–hedenbergite, rinkite, late magmatic eudialyte and magnesioarfvedsonite formed at ∼700°C with maximum a SiO 2 of 0.60. In contrast, a deuteric assemblage (400–348°C) is represented by aegirine–jadeite-rich clinopyroxene, post-magmatic eudialyte, sodalite, analcime and the decomposition...

... and tetraferriphlogopite, groundmass potassic amphiboles, Sr-rich apatite and monazite-(Ce), late stage Na-poor K-feldspar and quartz. The rocks differ in terms of the character of the amphiboles (Ti-potassian arfvedsonite vs . K-richterite-K-magnesioarfvedsonite-K-arfvedsonite solid solution), spinel compositions...

..., yielding forsterite ( f = 5.1 % ), and serpentine substitution by diopside, magnesioarfvedsonite, and tremolite takes place. Tectonites, containing ultra basic rocks, granites, and graphite flotoconcentrates, are studied with an emphasis on their trace element composition. As compared with initial...

... of melt favored appearance of K-Ti-richterite, K-magnesioarfvedsonite, davanite, carbonates, and barite at the latest stages. In addition to silicate-melt inclusions, AI-spinel, fresh leucite, and sulfides (pentlandite, Ni-rich monosulfide solid solution, viola rite, chaIcopyrite, and pyrite) were also...

... parallel to (001) and (100) as commonly believed, even though X-ray single crystal photographs usually suggest host and lamellae share a common (001) or (100) lattice plane. Coexisting magnesioarfvedsonite and manga-noan cummingtonite, described in detail here, show an extreme example with lamellae 16...

... low sanidine form a fine-grained rock with no phenocrysts. The smallest amphibole crystals are platy limpid prisms of fluoro-potassic-magnesioarfvedsonite ∼0.02 mm×0.04 mm×0.10 mm in size, and with good X-ray diffraction quality. Associated minerals are Fe 3+ -bearing low sanidine, Sr-bearing fluor...

... apoharzburgite tectonites bear a newly formed phase developed after serpentine under the conditions of stability of graphite, acicular olivine, diopside, magnesioarfvedsonite, and tremolite; in addition, antigorite recrystallization and later serpentinization and carbonatization accompanied by the “burning-out...

... Magnesioarfvedsonite Eckermanite Riebeckite 2Vy= 380 - 65 0 , 2Va = 68° - 8)0, 2Vn 20° - 88°, 2Vn 68 0 , 2VCJ. = 30°, x = yellow, z = dark green 2Va= 50° 2Va 78° 2Vy = 85° Alkaline series Sevvattur basin Jogipaui basin K-feldspars (Average compositions) Or62AbJ4An4 Or17AbnAn) Compositional variations in clinopuroxenes...

...-microcline vein with nepheline, ussingite, murmanite, and magnesioarfvedsonite cropping out in the “Severny” loparite quarry ( Yakovenchuk et al. 2010 ). The outer zone of the pegmatite (up to 80 cm thick) are composed of large blocks of microcline, nepheline, sodalite, and eudyalite penetrated by long...

... as predominately winchite and richterite, with only minor tremolite, and trace magnesioriebeckite and magnesioarfvedsonite ( Meeker et al. 2003 ). As part of a much larger project dealing with the legal issues surrounding the deposit and the possible contamination of soils in the town of Libby, we started...

.... Schiellerup H. Njange F. ( 2008 ): Solid solution between potassic-obertiite and potassic-fluoro-magnesioarfvedsonite in a silica-rich lamproite from northeastern Mozambique . Eur. J. Mineral. , 20 , 1011 – 1018 . Robinson P. Solli A. Engvik A. Erambert M. Bingen B...

...). The mean modal composition of the rock is Kfs 40 Nph 30 Aeg 20 Eud 10 . Other minor rock-forming minerals include sodalite, natrolite, and magnesioarfvedsonite. Characteristic accessory minerals are murmanite, loparite-(Ce), pyrochlore, thorite, anatase, baryte, rhabdophane-(Ce), pyrrhotite, chalcopyrite...

.... The selvage of the lens consists of large crystals of microcline with interstitial nepheline, sodalite, eudialyte, generally replaced by catapleiite, lovozerite and zircon, keldyshite, aegirine, magnesioarfvedsonite, lorenzenite, lomonosovite and beta-lomonosovite, loparite-(Ce) and pyrochlore. The walls...

... the associated minerals at Mount Kedykverpakhk are natrolite, microcline, albite, aegirine, nepheline, arfvedsonite, sodalite, eudialyte, and lorenzenite; at Mount Lepkhe-Nelm, with microcline, aegirine, nepheline, magnesioarfvedsonite, eudialyite, lorenzenite, lamprophyllite, catapleiite, and others; at Mount...

... linearity with the end-member compositions in Figure 6 is for crystal 793, which is actually magnesioarfvedsonite; the deviation from linearity for 793 is still quite modest, and the different name is a result of a slight excess of A (Na + K) for the amount of Fe 3+ present, which just moves the crystal...

... – 570 . Robinson , P. , Solli , A. , Engvik , A. , Erambert , M. , Bingen , B. , Schiellerup , H. and Njange , F. ( 2008 ) Solid solution between potassic-obertiite and potassic-fluoro-magnesioarfvedsonite in a silica-rich lamproite from northeastern Mozambique...

...-magnesioarfvedsonite corner, because of the presence of 0.4 O apfu substituting for (OH, F). This result is slightly misleading, because the diagram is constructed with ideal formulae having full A occupancy and B Na = 2 apfu, whereas the actual rim formulae have B Ca = 0.19–0.24, A ions = 0.79–0.92, and W O = 0.42...