feldspar

How To Use feldspar In A Sentence

• The main constituent phases of these rocks are plagioclase, hornblende, pyroxene, quartz and K-feldspar, and accessory phases include magnetite, sphene, zircon and apatite.
• The flake mica produced in the U.S. comes from several sources: the metamorphic rock called schist as a by-product of processing feldspar and kaolin resources, from placer deposits, and from pegmatites. Mica
• Various potassium silicates -- leucite, feldspar, sericite, and glauconite -- and the potassium sulphate, alunite, have received attention and certain of them have been utilized to a small extent, but none of them are normally able to compete on the market. The Economic Aspect of Geology
• The unit is an orange/red-weathered ignimbrite, which is generally massive and strongly feldsparphyric.
• From Pliocene time the shallow emplacement of intrusive bodies resulted in thermal metamorphism (forming, for example, biotite, cordierite, andalusite, K-feldspar and corundum in pelites) and hydrothermal activity.
• The mineral assemblage comprises quartz, K-feldspar, albitic plagioclase, white mica, apatite, tourmaline and garnet.
• The province is also endowed with other non-traditional minerals including nickel, feldspar, emerald, limestone, granite, amethyst, sodalite and syenite.
• Figure parts a-e with crossed nichols. (a) Micrographic groundmass surrounds feldspar phenocryst fragment. (b) Micrographic groundmass around clinopyroxene phenocryst. Granophyre_photos.html
• So much for the western line; in the Portillo pass, proceeding eastward, we meet an immense mass of conglomerate, dipping to the west 45 deg, which rest on micaceous sandstone, etc., etc., upheaved and converted into quartz-rock penetrated by dykes from the very grand mass of protogine (large crystals of quartz, red feldspar, and occasional little chlorite). More Letters of Charles Darwin — Volume 1
• The feldspar statue keeps intent, slit-eyed watch over a tomb.