(n.) Common or potash feldspar crystallizing in the monoclinic system and having two cleavages at right angles to each other. See Feldspar.
Example Sentences:
(1) The authors have found out that fly-ashes included mainly quartz, orthoclase and mullite.
(2) These strains possess better ability to utilize the orthoclase and biotite.
(3) All the ashes have been found to contain: quartz and mullite, 3 ashes contained additionally orthoclase, whereas 1, apart from quartz and mullite, contained kaolinite; naturally radioactive elements (Ra226, K40, Th228) and trace elements (As, Ba, Be, Cd, Ce, Cu, Fe, Pa, Mo, Ni, Pb, Se, U Zu).
(4) In all ash samples alpha-quartz and mullite were found: in some of them also kaolinite and orthoclase were traced.
(5) The following crystalline phases were determined in the materials: kaolinite, illite, quartz, orthoclase and microline.
(6) It was impossible to ascertain whether these synthetic crystals may be sanidine, orthoclase, or microcline.
Pegmatite
Definition:
(n.) Graphic granite. See under Granite.
(n.) More generally, a coarse granite occurring as vein material in other rocks.
Example Sentences:
(1) A wide spectrum of heterotrophic and autotrophic microorganisms was detected in the zones of decomposition of spodumene and bed rocks, pegmatites and shales, in the spodumene deposit.