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Related to microcline: sanidine, orthoclase


see feldsparfeldspar
or felspar
, an abundant group of rock-forming minerals which constitute 60% of the earth's crust. Chemically the feldspars are silicates of aluminum, containing sodium, potassium, iron, calcium, or barium or combinations of these elements.
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a mineral of the feldspar group. It is a triclinic K-Na feldspar with the chemical composition (K, NaXAlSiaOg]; it contains negligible quantities of Ca, Ba, Fe, Rb, and Cs. Microcline often forms perthites, which are microclines with small albite intergrowths. It occurs as individual grains, grain aggregates, prismatic crystals, or single crystals with a volume up to several m3. The mineral has a hardness of 6–6.5 on Mohs’ scale and a density of 2,540–2,570 kg/m3. It may be pink, brownish yellow, reddish white, or pinkish red; less frequently it is white or bluish green (amazonite, or amazonstone). Microcline has a vitreous or pearly luster. A thin section of the mineral under the microscope shows multiple twins, forming the characteristic microclinic grating structure.

Microcline is a typical rock-forming mineral contained in granite, granodiorite (syenite), pegmatite, and gneiss. It is the primary raw material used by the ceramics industry (porcelain, glazed pottery, and industrial ceramics). Amazonite is used as an ornamental stone.


Kostov, I. Mineralogiia. Moscow, 1971. (Translated from English.)


KAlSi3O8 A triclinic potassium-rich feldspar, usually containing minor amounts of sodium; may be clear, white, pale-yellow, brick-red, or green, and is generally characterized by crosshatch twinning.
References in periodicals archive ?
It is agreed that microcline feldspars is derived from plutonic igneous and metamorphic rocks.
Behaviour of different particle size fractions in the flotation of calcite from wollastonite and microcline, Minerals Engng.
The total amount of feldspar is 10 present in which 02 % orthoclase, 01 % plagioclase and 07 % microcline.
13789) granite with the occurrence of large grains (up to 10 mm) of microcline (no.
Petrographic studies of the rocks revealed a plethora of minerals including biotite, hornblende, quartz, muscovite, microcline and plagioclase feldspar and some accessory minerals, Figure 2.
Foster occurs in miarolitic cavities containing gem-quality fluorite, microcline, phenacite ([Be.
The K-feldspar has local development of mottled texture due to variable inversion to triclinic microcline, and quartz has rare subgrain development.
Patchy extinction displayed by some of the feldspar grains may be indicative of the potassium-rich feldspar, microcline ([KAISi.
Detailed petrographic and XRD studies reveal that all the samples are predominantly composed of quartz and carbonates (mainly calcite) with subordinate feldspars (plagioclase and microcline varieties) as detrital matrix/ cement in all the samples.
2] treatment may lead to a release of considerable amounts of Si from smectite; somewhat less Si is released from kaolin and microcline.
The results of petrographic study of the lithofacies-3 demonstrated that the quartz was in the range of 50 to 88 (Percent) in addition to muscovite flakes (0-2 (Percent) , plagioclase and microcline grains (2 (Percent) and the rock fragments (about 1 (Percent) could be derived from Sargodha Karana Hills of Indian shield (Shah, 2009; Qureshi, et al.