
	Where results make sense

Topic: Microcline

Related Topics

Orthoclase

Rock (geology)

Muscovite

Hornblende

List of minerals

Olivine

Alum

Mohs scale of mineral hardness

Diamond

Barium

List of rocks

Allies

Richter scale

Kublai Khan

List of chemistry topics

In the News (Mon 13 Feb 12)

EXECUTIVE POWER

Iran

ANALYSIS

Pakistan

Family compact

	MICROCLINE - LoveToKnow Article on MICROCLINE (Site not responding. Last check: 2007-10-08)
		In addition to being twinned according to the same laws as orthoclase, microcline is repeatedly twinned according to the albite-law and the pericline-law, producing a very characteristic grating or cross-hatched structure which is especially prominent when thin sections of the mineral are examined in polarized light.
		Microcline occurs, usually with orthoclase, as a constituent of pegmatites, granites and gneisses; it is rare in porphyries and is not known in volcanic rocks.
		Closely allied to microcline is the anorthic soda-potash-feldspar known as anorthoclase or natron-microcline.
	www.1911encyclopedia.org /M/MI/MICROCLINE.htm (383 words)

	Microcline in Michigan
		Farther north microcline is characteristic of the mineralization in the Osceola.
		The relation observed by the writer between the microcline and sericite which occur in close association in the Arcadian and Superior lodes is significant because of the light it sheds on the process of ore deposition.
		The writer has found microcline from a vug in a pegmatite at Pala, California, showing similar twinning, and is inclined to believe that further study may show pneumatogenic and hydrogenic microcline to be commonly of this nature.
	www.minsocam.org /MSA/collectors_corner/arc/mimicrocline.htm (2537 words)

	Feldspar (Site not responding. Last check: 2007-10-08)
		Amazon stone, or amazonite, is a beautiful green variety of microcline.
		It is not found anywhere in the Amazon basin, however, Spanish explorers who named it apparently confused it with another green mineral from that region.
		The members of this series are known as the soda-lime (or lime-soda) feldspars, and as a group are called the plagioclase feldspars (from the Greek meaning "oblique fracture," in reference to the two not-quite-right-angle cleavages).
	www.1-free-software.com /en/wikipedia/f/fe/feldspar.html (646 words)

	microcline -- Britannica Concise Encyclopedia - The online encyclopedia you can trust!
		Microcline is found at Baveno, Italy; Kragerø, Nor.; Madagascar; and, as amazonstone, in the Urals, Russia, and Florissant, Colo., U.S. For detailed physical properties, see feldspar (table).
		Microcline is the form of potassium feldspar that is stable at the lowest temperatures.
		Microcline forms a series of mixtures with the plagioclase albite, the sodium atoms of which replace the potassium atoms in the microcline structure.
	www.britannica.com /ebc/article-9052498 (560 words)

	MYRMEKITE 37 of 50
		The microcline granites are typical of Precambrian areas, but the orthoclase granites are sporadic and characterized by being in younger alpine regions or are rapakivi granites.
		Collins (1997c, 1998a) further suggested that where K replaces Na and Ca in triclinic plagioclase, the triclinic microcline would result by inheriting the triclinic lattice from the plagioclase and leave irregular islands of perthite lamellae of various sizes and in seemingly random distributions because of differential incomplete replacements.
		Because the microcline granite, created by replacement processes, inherits the features of the original mafic rock, e.g., primary hypidiomorphic textures, enclaves, sharp contacts, and cross-cutting dikes, as well as any metamorphic aureole in the wall rocks, these features can still be preserved just as the microcline inherits its triclinicity from the plagioclase which it replaces.
	www.csun.edu /~vcgeo005/Microcline.htm (2509 words)

	Pennsylvania Geological Survey: Open-File Reports – Kennett Square Report Text
		In the Woodville Nappe, the Baltimore Gneiss consists of felsic gneiss and biotite schist in varying proportions, from felsic gneiss with biotite laminae to biotite schist with pods and layers of felsic gneiss.
		The marble is primarily carbonate, with minor diopside, muscovite, microcline, and quartz.
		The Bayard microcline gneiss and Wyndemere microcline gneiss are mapped as lenses within the “Glenarm Wissahickon” formation and the Cockeysville Marble, respectively, because the folds required to bring them into their present positions while remaining part of the Setters Formation are unrealistically complex.
	www.dcnr.state.pa.us /topogeo/openfile/kstext.aspx (1453 words)

	april-03-8
		The only gem variety of microcline feldspar is the verdigris-green to blue —green material to which the name amazonite or amazon stone is applied.
		Microcline also occurs in translucent to opaque well formed crystals or as massive material of grayish-white, flesh to brown-red or green color.
		The green microcline feldspar owes it variety name amazonite to the Amazon River, although it is not known to come from the vicinity of the Amazon.
	www.discoveret.org /kgms/april-03/april03-8.html (990 words)

	The Baringer Hill, Texas, Pegmatite
		The microcline is visibly perthitic and the percentage of albite is materially greater than in the graphic granite microcline.
		The writer believes that this transverse albite is older albite which was present in the microcline perthite of the normal pegmatite, and that the tabular albite has replaced the perthite to such an extent that the original microcline has almost disappeared.
		The minerals of the normal pegmatite, microcline and quartz, are of course of greatest quantitative importance.Where the normal pegmatite lies in contact with the red rock the border between the two is a replacive one with quartz and microcline the host minerals (Fig.
	home.satx.rr.com /robnjean/bh/landes1.html (2735 words)

	Rocks & Minerals: Recent Findings of Unique Mineralogical Specimens on the KOLA Peninsula (Site not responding. Last check: 2007-10-08)
		In interstices between microcline crystals are found elongated prismatic, translucent crystals of lorenzenite (to 2 cm long and 4 mm thick) and intergrowths of brown crystals of sphalerite (to 3 cm in diameter).
		Within the microcline and in cavities there are thin, tabular crystals of ilmenite (to 4 cm in diameter and 5 mm thick), frequently entirely replaced by aggregates of dark blue anatase and fl oxides of manganese.
		Some interstices in aggregates of microcline are filled with clusters of tiny pale yellow crystals of ancylite-(Ce), bright to dark blue mosaic crystals of anatase (to 0.3 mm), or colorless crystals of natrolite (to 3 cm long).
	www.findarticles.com /p/articles/mi_m0GDX/is_1_76/ai_69201588/pg_2 (1355 words)

	Orthoclase (Site not responding. Last check: 2007-10-08)
		Microcline tends to be deeper-colored and is the only one that can be, but is not always, a blue-green color (amazonite).
		Orthoclase does not show the lamellar twinning that is common in microcline and is occassionally present as striations on cleavage surfaces.
		In microcline the ions are ordered, and this produces the lower symmetry of triclinic (yes, more order produces lower symmetry, see discussion in symmetry).
	www.seismo.berkeley.edu /~jill/wisc/moreorth.html (423 words)

	The feldspar microcline
		The crystals of Microcline are very similar to those of Orthoclase, and form the same twins.
		Crystals of Microcline are generally much larger than those of Orthoclase, and deep green is a sure sign of Microcline, since Orthoclase does not exist in deep green examples.
		Microcline is important in the manufacture of glass and ceramics.
	www.minerals.net /mineral/silicate/tecto/feldspar/microcln.htm (506 words)

	MICROCLINE Factsheet & Information Page at mineralminers.com
		Microcline commonly occurs in plutonic igneous rocks such as granites and syenites that cooled slowly and at considerable depth.
		Microcline is distinguished in thin section from orthoclase (the medium temperature polymorph of potassium feldspar which is chemically identical to microcline) by the presence of tartan twinning.
		Microcline is said to stimulate clarity of thought, to enhance understanding, and to improve one's ability to cooperate with others.
	www.mineralminers.com /html/micminfo.htm (766 words)

	Table of lithologic units html (Site not responding. Last check: 2007-10-08)
		Beneath this rind is a continuous layer, 0.3-2 m, composed of a coarser aggregate of the same minerals.
		This zone is composed of an even-grained (1-10 cm) aggregate of primary quartz, microcline, spodumene, finer albite, and scattered millimeter-size uranium-rich microlite crystals.
		This zone, dominated by large blocks (0.5-2 m) of cream to pale orange-colored perthitic microcline, occupies basal sections of the dike.
	epswww.unm.edu /harding/mineral/lith_tbl.htm (523 words)

	geoahead: Earth Science on your desktop (Site not responding. Last check: 2007-10-08)
		Anorthoclase, albite, perthite, orthoclase and microcline are triclinic.
		Orthoclase and microcline appear to be monoclinic externally because of twinning.
		In microcline cross-hatch due to twinning is often visible under the microscope.
	www.geoahead.com /mineral/alkali_feld.cfm (422 words)

	MYRMEKITE 38 OF 50
		As the coalesced microcline areas (as seen in thin section) increase in grain size, tiny islands of plagioclase occur locally and are in optical parallel orientation with themselves and/or with a larger plagioclase inclusion inside the microcline (Fig.
		The objection to this possibility occurring in the Monterey microcline megacrysts is the presence of adjacent plagioclase inclusions with inclined lattices having scalloped or irregular borders.
		During the shearing and volume adjustments that occurred where microcline crystals were formed, the granulation of weakened adjacent plagioclase crystals whose lattices were inclined to the plane of shearing created many small fragments some of which were parallel to the lattice of the growing megacryst.
	www.csun.edu /~vcgeo005/Monterey2.html (6695 words)

	Amazonite (Microcline) (Site not responding. Last check: 2007-10-08)
		Microcline is a common, but not a well known mineral that has been used as a semi-precious stone under the names of Amazonite and Perthite.
		Amazonite is a variety that is deep green and is suitable for carving and polishing.
		The perthite variety is stripped, the colored stripes are microcline and the white or clear stripes are a plagioclase feldspar.
	www.nfobase.com /html/amazonite__microcline_.html (541 words)

	MFA - CAMEO - Material Description (Site not responding. Last check: 2007-10-08)
		Under a polarizing microscope, microcline displays a minute multiple twinning that forms a grating-like pattern.
		Amazon stone, or amazonite, is a green microcline that has been used since antiquity for decorative items.
		Microcline is used in making glass, porcelain, and enamel.
	www.mfa.org /_CAMEO/FRONTEND/fullrecord.asp?name=microcline (123 words)

	MICROCLINE (Potassium Aluminum Silicate)
		The colored stripes are microcline and the white or clear stripes are plagioclase feldspars.
		Microcline is a polymorph of other minerals that share the same chemistry but have different crystal structures.
		Microcline can be found as a major rock forming component in granites, syenites and in metamorphic gneisses.
	mineral.galleries.com /minerals/silicate/microcli/microcli.htm (543 words)

	Pennsylvania Geological Survey
		Rocks identified with the Setters Formation in Chester County, PA include three lithologies that correspond to members in MD-DE: microcline gneiss – 50-80% microcline with quartz, biotite, and locally abundant post-kinematic muscovite; quartzite – quartz with minor microcline and biotite; pelitic schist – quartz, biotite, muscovite, plagioclase, microcline, sillimanite, garnet and tourmaline.
		The microcline gneiss has some trace element and REE characteristics similar to alkaline igneous rocks, and may be of volcanic or volcaniclastic origin.
		A marble layer approximately 500 m thick lies between the quartzite and microcline gneiss of the Setters north of the Avondale Massif.
	www.dcnr.state.pa.us /topogeo/gsaabstr/setters.aspx (428 words)

	Alkali Feldspar Series Members
		Orthoclase crystallizes in the same crystal system and class as sanidine and anorthoclase (monoclinic 2/m) but the distribution of Al and Si in orthoclase is partially ordered in orthoclase due either to the lower temperature or crystallization or to a slower rate of cooling.
		The distribution of Al and Si in microcline is completely ordered on the two tetrahedral sites and the exsolution lamellae are often large enough to see without a microscope.
		Microcline typically forms in intrusive rocks, especially pegmatites, that cooled extremely slowly.
	www.utexas.edu /tmm/npl/mineralogy/Science_of_Minerals/AlkalFfeldsparSeries.htm (521 words)

	Amie Garcia Public Absract
		Microcline is the dominant mineral within the pegmatite and is tan to green in color.
		The CL study indicates that the tan-colored microcline formed first, and was changed to amazonite as the pegmatite solidified.
		This change in color was due to the interaction of Pb (lead) present in the microcline structure and fluids that entered fractures in the mineral.
	www.nmnh.si.edu /rtp/students/2004/students_2004_garcia.html (247 words)

	Example 6.-- Reaction-Path Calculations
		Selected results for simulations A1-A4 are presented in table 14 and are plotted on figure 2 as points A, B, D, and F. The stability fields for the phases, which are based on the thermodynamic data, are outlined on the figure and are not calculated by the modeling in these simulations.
		In simulation A5, point C is calculated by allowing microcline to dissolve to a point where kaolinite is at saturation and is present in the phase assemblage, while gibbsite is at saturation, but not present in the phase assemblage.
		A simpler approach to determining the reaction path is simply to react microcline incrementally, allowing the stable phase assemblage among gibbsite, kaolinite, muscovite, and microcline to form at each point along the path.
	wwwbrr.cr.usgs.gov /projects/GWC_coupled/phreeqc.v1/html/phqc_57.htm (1084 words)

	Feldspar
		Microcline - white, pink, pale yellow, or sometimes green-blue, and not transparent.
		Orthoclase got is name from the Greek phrase meaning "straight fracture", Microcline from a Greek phrase meaning "small incline", and Plagioclase from the Greek phrase meaning "oblique fracture".
		Microcline - variety amazonite, is sometimes cut into cabochons, and used in jewelry.
	www.theimage.com /gemstone/feldspar/feldspar.html (472 words)

	LAS BRISAS Formation (Site not responding. Last check: 2007-10-08)
		It follows an interval of gneiss with abundant microcline porphyroblasts in a recrystallized calcareous matrix with interbeddings made-up of carbonates.
		The microcline gneiss associatea with limestone is distinguished from Aguerrevere and Zuloaga's "Zenda phase" by Smith, and placed by the same author, further-up in the section.
		The microcline gneiss outcrops, typically, in the hills surrounding the Baruta Valley and extends, mainly, towards the west.
	www.pdvsa.com /lexico/1edic/l66ii.htm (2144 words)

	A LARGE PURE GRAPHIC-GRANITE PEGMATITE, THE FUSION PRODUCT OF META-RHYOLITE AT THE ZERO FAULT, NEW JERSEY (Site not responding. Last check: 2007-10-08)
		The pegmatite is unzoned and is emplaced between layers of Proterozoic marble and microcline gneiss.
		The microcline gneiss is composed of microcline and quartz with variable concentrations of pyrite, mica, chlorite, and graphite.
		We, therefore, propose that the protolith of the microcline gneiss was rhyolitic rock that may be genetically related to Byram Granite exposed near Franklin, New Jersey.
	gsa.confex.com /gsa/2003NE/finalprogram/abstract_50916.htm (444 words)

Try your search on: Qwika (all wikis)