| These crystals were abundant in a very micaceous pegmatitic rock composed of muscovite, albite, and quartz with accessory schorl crystals. |
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| The phenakite is also associated with albite, limonite, smoky quartz, and topaz and is often overlooked because it resembles quartz. |
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| The quartz and albite contain small dark inclusions of cassiterite and columbite-tantalite-group minerals. |
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| The composition studied has very low albite and is classified as transitional between olivine nephelinite and nepheline-rich basanite. |
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| The lake may have dried up or nearly dried up periodically, producing outward concentric zones of albite, analcime, clinoptilolite, and smectite. |
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| Mylonitic rocks usually have ribbon quartz and rotated albite porphyroclasts. |
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| A plagioclase feldspar, albite probably, occurs as parallel growths of transparent colorless to yellowish crystals. |
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| Here it was associated with quartz, albite, schorl, muscovite, and microcline in the intermediate zone. |
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| All three are dominated by unaltered muscovite, quartz, K-feldspar and albite, with minor epidote. |
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| Well-formed crystals of quartz, microcline, and albite typically line pocket walls. |
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| White intergrowths of albite crystals are a common associate of amazonite and smoky quartz. |
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| The phyllites show fine-grained foliated textures and the mineral assemblage consists of chlorite, muscovite, albite, chloritoid and garnet along the main foliation. |
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| The first phase of diagenetic albite constitutes an impure, turbid variety including albitized grains of original plagioclase and alkali feldspar. |
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| Typical minerals in this facies are quartz, albite, prehnite, pumpellyite, chlorite, stilpnomelane, muscovite, and actinolite. |
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| Characteristic minerals include quartz, muscovite, biotite, chlorite, andalusite, actinolite, calcite, dolomite, albite, and epidote. |
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| The liquid could theoretically reach the pure Ab composition at 1,100 °C, where it will disappear into the crystallizing albite. |
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| The amazonite occurs in miarolitic cavities in granite as single crystals and crystal groups and is often associated with other minerals, especially albite and smoky quartz. |
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| It was first collected by Quintin Wight in 1994 at a contact between a vein of fine-grained albite and the host rock, nepheline syenite. |
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| It may also be found in low-grade metamorphic rocks and as authigenic albite in certain sedimentary varieties. |
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| Orthoclase, albite, quartz, and biotite may be found in an igneous granite. |
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| Two common kinds of twinning those designated Carlsbad twinning and albite twinning are shown in the figure. |
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| It is associated mainly with pectolite, albite, arfvedsonite, calcite, fluorite, and apophyllite. |
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| Calcic amphiboles, including hornblende and actinolite are abundant, and probably are alteration products, which also include albite, orthoclase and rare pyrite. |
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| Brookite is best known from alpine-cleft-type occurrences, where it is round with anatase, rutile, titanite, quartz, adularia, albite, hematite, calcite, and chlorite. |
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| They collected several pegmatite pockets in which topaz was associated with both clear and smoky quartz, microcline, albite, muscovite, fluorite, and cassiterite. |
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| Two-feldspar thermometry fails to retrieve peak temperatures from these rocks owing to late stage unmixing reducing the albite content of orthoclase. |
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| The microgranite has a felsitic groundmass containing microphenocrysts of albite and orthoclase along with phenocrysts of corroded quartz and sporadic dihedral garnet. |
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| In the spectra of exposed specimens, peaks due to gismondine be came quite prominent including those of albite and chabazite. |
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| A few albite and quartz-feldspar dykes crosscut the local stratigraphy. |
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| Associated Minerals include albite, dolomite and elpidite. |
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| Specular hematite, albite, adularia, and quartz fill voids and form veins, and also occur as granulated fragments in the groundmass. |
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| Gaidonnayite also occurs in altered pegmatite dykes mainly with catapleiite, elpidite, hilairite, albite, microcline, chlorite, aegirine, epididymite, and goethite. |
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| Plants are shallowly and weakly rooted in a silt soil containing biotite mica and albite feldspars. |
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| The following major and minor minerals were identified in the samples examined: quartz, orthoclase, albite, anorthite, biotite, muscovite, garnet, secondary chlorite, kaolinite, magnetite, ilmenite, hematite, and apatite. |
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| We note that whereas the clinopyroxene is fresh, the plagioclase is variably altered to albite and stilbite. |
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| Members of the plagioclase feldspar series range from almost pure white in albite through light gray to darker gray toward the anorthite end-member. |
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| Associated minerals include microcline, aegirine, dawsonite, rhodochrosite, sodalite, natrolite, albite, sérandite, siderite, taeniolite, catapleiite, astrophyllite, genthelvite, and a franconite-group mineral. |
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| In the case of the alkali feldspar minerals, thin white albite layers will alternate between typically pink microcline. |
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| The alteration consists primarily of a hematite, carbonate, albite, and sericite assemblage with the presence of pyrite being a strong indicator of the gold mineralization. |
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| The mineral Cleavelandite, a variety of albite, was named after him. |
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| These rocks in petrology studies have nemato-plastic texture and have been transformed into Tremolite, Actinolite and Albite schist. |
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