Results 11 to 20 of about 868 (182)
Rubidian microcline from Red Cross Lake, northeastern Manitoba [PDF]
Bulletin of the Geological Society of Finland, 1985 Dark grey, slightly perthitic and grid-twinned to non-perthitic and Baveno-twinned, near-maximum rubidian microcline occurs in sheared dikes of pollucite-bearing pegmatites at Red Cross Lake, northeastern Manitoba.
P. Černý, H. Pentinghaus, J.J. Macek
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Rubidium-rich feldspars and associated minerals from the Luolamäki pegmatite, Somero, Finland [PDF]
Bulletin of the Geological Society of Finland, 1998 Rubidium feldspar occurs near the core zone of the highly fractionated petalite-subtype Luolamäki granitic pegmatite in intimate intergrowth with other feldspars which are part of a characteristic sequence of alteration of pollucite.
D.K. Teertstra +2 more
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Brazilian Journal of Geology, 2022 The Serra Branca pegmatite in northeastern Brazil is unique because of its megacrysts of bluish-green amazonite currently exploited for ornamental purposes and as high-quality gemstones.
Glenda Lira Santos +5 more
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Ice nucleation activity of silicates and aluminosilicates in pure water and aqueous solutions – Part 1: The K-feldspar microcline [PDF]
Atmospheric Chemistry and Physics, 2018 Potassium-containing feldspars (K-feldspars) have been considered as key mineral dusts for ice nucleation (IN) in mixed-phase clouds. To investigate the effect of solutes on their IN efficiency, we performed immersion freezing experiments with the K ...
A. Kumar, C. Marcolli, B. Luo, T. Peter
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MINERALOGY OF APATITE-AEGIRINE-MESOPERTHITE PEGMATITES OF MINE NO. 243 OF THE ILMENY STATE RESERVE (SOUTH URALS) [PDF]
Минералогия, 2023 The paper describes mineralogy of apatite-aegirine-mesoperthite pegmatites, which are located in a fenite halo at the southeastern contact of the Selyankino syenite block (Ilmeny State Reserve, South Urals). Two pegmatite veins are exposed by mines.
E.P. Makagonov +2 more
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Heliyon, 2021 This study presents the K-Ar geochronology for hydrothermal K-feldspar in plagioclase alteration, including methodology and application to the Toki granite, in central Japan.
Takashi Yuguchi +3 more
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Geologia Croatica, 2011 Potassium feldspars from different granitoids and gneisses of Papuk Mt. (Slavonia, Croatia) have been investigated by X-ray powder diffraction. Diffraction patterns classically observed as well as patterns calculated by Rietveld refinement were compared ...
Marija Horvat +3 more
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Ice nucleation properties of K-feldspar polymorphs and plagioclase feldspars [PDF]
Atmospheric Chemistry and Physics, 2019 The relation between the mineralogical characteristics of size-selected feldspar particles from 50 to 800 nm and their ability to act as ice-nucleating particles (INPs) in the immersion mode is presented.
A. Welti +3 more
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Molecules, 2022 Fulgurites are naturally occurring structures that are formed when lightning discharges reach the ground. In this investigation, the mineralogical compositions of core and shell compartments of a rare, iron-rich fulgurite from the Mongolian Gobi Desert ...
Ahmet Karadag +7 more
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The Tonigala granite, N. W. Ceylon [PDF]
Bulletin of the Geological Society of Finland, 1971 A pink, microcline granite at Tonigala in north-western Ceylon occurs as a concordant sheet, one to two miles wide and about 10 miles long, in a complex of migmatitic and granitic biotite and biotite-hornblende gneisses belonging to the PreCambrian ...
P.G. Cooray
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