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	Pyroxene - Wikipedia, the free encyclopedia
		The upper mantle of Earth is composed mainly of olivine and pyroxene.
		Pyroxene and feldspar are the major minerals in basalt and gabbro.
		The chain silicate structure of the pyroxenes offers much flexibility in the incorporation of various cations and the names of the pyroxene minerals are primarily defined by their chemical composition.
	en.wikipedia.org /wiki/Pyroxene (910 words)

	Pyroxene - LoveToKnow 1911 (Site not responding. Last check: 2007-10-12)
		The name pyroxene was originally given by R. Haiiy in 1796 to the fl crystals of augite found in the lavas of Vesuvius and Etna: he derived the name from the Greek irvp (fire) and vos (a stranger), because he thought that the crystals had been accidentally caught up by the lavas which contained them.
		As a matter of fact, the pyroxenes are, next to the felspars, the commonest constituents of igneous rocks of almost all kinds, being especially characteristic of those of basic composition.
		By decomposition the rocks consisting of pyroxene pass into serpentines, which sometimes preserve the original structures of the primary minerals, such as the lamination of hypersthene and the rectangular cleavage of augite.
	www.1911encyclopedia.org /P/PY/PYROXENE.htm (536 words)

	Pyroxene
		Pyroxenes are a group of the rock-forming silicate minerals.
		It was named thusly due to their presence in volcanic lavas, where they are sometimes seen as crystals embedded in volcanic glass; it was assumed that were impurities in the glass, hence the name "fire strangers".
		The mantle of Earth is composed mainly of olivine and pyroxene.
	www.ebroadcast.com.au /lookup/encyclopedia/py/Pyroxene.html (152 words)

	Chondrule - Wikipedia, the free encyclopedia
		Most chondrules are composed primarily of the silicate minerals olivine and pyroxene, surrounded by feldspathic material that may either by glassy or crystalline.
		When the pyroxene fibers are coarser, they may appear to radiate from a single nucleation site on the surface, forming a radial or excentroradial texture.
		In these, grains of olivine and/or pyroxene are equidimensional and sometimes euhedral.
	en.wikipedia.org /wiki/Chondrule (930 words)

	Amethyst Galleries - PYROXENE GROUP
		The pyroxenes are closely related to a group of inosilicates called the pyroxenoids.
		The pyroxenes are an important group among the single chained inosilicates.
		Pyroxenes are sometimes seen as crystals embedded in volcanic glass and the assumption was that they are impurities in the glass, hence the term "fire strangers".
	mineral.galleries.com /minerals/silicate/pyroxene.htm (331 words)

	zagami
		Raman peak positions of Zagami pyroxenes are plotted on the field of lunar pyroxenes, for which the correlation of Raman peak positions with cation ratios were established.
		The points for Zagami pyroxene lie along the same broad curve observed for lunar pyroxenes and are cover a range in Mg# from ~0.3 to ~0.6, which is consistent with literature studies.
		The pyroxenes are strongly zoned, and the texture of the rock is basaltic.
	epsc.wustl.edu /haskin-group/Raman/zagami.htm (368 words)

	Pyroxene - definition of Pyroxene - Labor Law Talk Dictionary (via CobWeb/3.1 planetlab2.cs.umd.edu) (Site not responding. Last check: 2007-10-12)
		Pyroxene is an essential constituent of many rocks, especially basic igneous rocks, as basalt, gabbro, etc.
		The names of the common calcium - iron - magnesium pyroxenes are defined in the 'pyroxene quadrilateral' shown in figure 1.
		A second important series of pyroxene minerals are the sodium baring pyroxenes who's nomenclature is shown in figure 2.
	encyclopedia.laborlawtalk.com.cob-web.org:8888 /Pyroxene (969 words)

	pyroxene
		The pyroxene mineral group is of particular interest in planetary sciences.
		Determining the compositional and structural characteristics of pyroxenes in rocks can be crucial to understanding their petrogenesis.
		Peak positions of orthorhombic pyroxenes plot at the highest values of Mg cation fraction and peak positions of triclinic pyroxenoids plot at the lowest values.
	epsc.wustl.edu /haskin-group/Raman/pyroxene.htm (610 words)

	TES NEWS, v. 4, n. 2, pyroxenes
		"Pyroxene" is a general term used to refer to a whole class of minerals that have the same crystal structure, but different chemical compositions.
		Pyroxenes found in volcanic rocks are made of silicon and oxygen plus magnesium, iron, calcium (and magnesium or iron), or some combination of magnesium and iron (with or without calcium).
		Therefore, the presence of certain pyroxenes in a basaltic rock can tell a geologist a lot about the conditions under which the original magma was generated.
	tes.asu.edu /TESNEWS/4_VOL/No_2/pyroxene_veh.html (873 words)

	Pyroxene Data (Site not responding. Last check: 2007-10-12)
		The pyroxenes are a family of iron-magnesium silicate minerals that are important in igneous and metamorphic rocks, particularly those with a more mafic (iron-magnesium rich) composition formed at higher pressures and temperatures.
		Pyroxene minerals i nclude aegirine, augite, diopside, hedenbergite, enstatite, jadeite and spodumene.
		Other distinguishing properties: The pyroxenes may be mistaken for the amphiboles; however, the two cleavages in amphiboles are at oblique angles of around 60° - 120° and amphiboles (i.e., hornblendes) commonly appear to be re ctangular or elongate crystals while pyroxenes (e.g., augite) are more stubby and equi-dimensional.
	www.uwm.edu /Course/422-100/Mineral_Rocks/pyroxene.data.html (160 words)

	Composition and Stability
		The minerals that are present in a given rock are functions of 1) which minerals or possible combinations of mineral are stable, and 2) the bulk composition of the rock.
		The figure shows that under conditions where pyroxene is stable a relatively Fe-rich rock composition such as a will exhibit the minerals olivine and pyroxene, and a relatively Si-rich rock composition such as b will exhibit the minerals quartz and pyroxene.
		Under conditions where pyroxene is not stable (i.e., where the above reaction runs from right to left), both compositions (a and b) would yield a rock containing olivine and quartz.
	darkwing.uoregon.edu /~jrice/geol_311/CompositionSpace.html (882 words)

	Mineralienatlas Lexikon - Mineralgruppe /Pyroxen
		Pyroxene haben eine Härte zwischen 5 und 6,5 sowie eine bleichgrüne bis bräunlichgrüne oder bronzene Farbe.
		Eine sehr ähnliche Mineralgruppe sind die Amphibole; Pyroxene unterscheiden sich von diesen jedoch in der Spaltbarkeit; die Spaltwinkel bei Pyroxenen liegen bei 90°, während sie bei Amphibol 120° betragen.
		Pyroxene sind sehr häufig gesteinsbildende Mineralien in quarzarmen magmatischen Gesteinen wie Basalt, Gabbro und Pyroxenit und repräsentieren damit Teile des Erdmantels.
	www.mineralienatlas.de /lexikon/index.php/Mineralgruppe/Pyroxen?redirectfrom=Pyroxen (210 words)

	pyroxene - Search Results - MSN Encarta
		Pyroxenes, group of silicate minerals that are closely related to each other in chemical composition and crystal form.
		Peridotite, igneous rock composed of pyroxene, olivine, and hornblende.
		It is the rock that makes up the earth's mantle.
	ca.encarta.msn.com /pyroxene.html (89 words)

	Pyroxene (Site not responding. Last check: 2007-10-12)
		Pyroxene is a silicate mineral with the general composition (Mg,Fe)SiO
		Though the basic formula is simple, it is said to be a complex class of minerals.
		It is said to a ferromagnesian or "mafic" mineral which has a high crystallization temperature and is formed early in the Bowen reaction series.
	hyperphysics.phy-astr.gsu.edu /hbase/geophys/pyroxene.html (72 words)

	Crystal structure of pyroxene (Site not responding. Last check: 2007-10-12)
		The pyroxenes have chains of Si tetrahedra oriented parallel to the c-axis.
		The tetrahedra are aligned in the chains in a zigzag pattern, but the chains are still only one tetrahedron wide.
		Pyroxene has good {110} prismatic cleavages that are parallel to the c-axis and are at almost 90° to each other.
	www.geo.ucalgary.ca /~tmenard/crystal/pyroxene.html (119 words)

	Union College Geology Department, Petrology page, lunar rocks and lunar thin sections, thin section images, ...
		In this view the elongate colorful minerals are mostly pyroxene, and the blocky ones mostly olivine.
		The skeletal olivines include the pink-and-orange crystal in the center, and the bluish grain in the upper right in which four masses of melt were trapped.
		The chemical zoning in the pyroxenes and olivines changes their birefringence (both minerals) and optic orientation (pyroxene only).
	www.union.edu /PUBLIC/GEODEPT/COURSES/petrology/moon_rocks/12002.htm (427 words)

	Pyroxene
		Pyroxenes and Olivines: Structural Implications of Shock-Wave Data for High Pressure Phases
		Variations in optical properties,: According to chemical composition, in the pyroxenes of the clinoenstatite-clinohypersthene-diopside-hedenbergite system...
		Analysis of the pyroxene sahlite, from the vicinity of New-Haven, Conn
	www.veryhappening.com /things/pyroxene (136 words)

	pyroxene - HighBeam Encyclopedia
		pyroxene, name given to members of a group of widely distributed rock minerals called metasilicates in which magnesium, iron, and calcium, often with aluminum, sodium, lithium, manganese, or zinc occur as X in the chemical formula XSiO
		The pyroxene minerals crystallize in three different systems—orthorhombic, monoclinic, and triclinic—but all have a fundamental prism with angles of 87° to 93° and cleavages parallel to the prism angles.
		They are commonly white, grayish white, greenish white, greenish fl, fl, or brown, but other varieties occur.
	www.encyclopedia.com /doc/1E1-pyroxene.html (269 words)

	Pyroxene (Site not responding. Last check: 2007-10-12)
		Pyroxene is one of the three main minerals that makes up basalt.
		The most common pyroxenes are magnesium, calcium, and iron silicates.
		A common pyroxene is augite which is very abundant in many igneous rocks such as basalt and gabbro.
	volcano.und.nodak.edu /vwdocs/vwlessons/lessons/Slideshow/Show1/Show1-14.html (40 words)

	PYROXENE - Online Information article about PYROXENE
		The name pyroxene was originally given by R. Haiiy in 1796 to the See also:
		primary origin in igneous rocks, the pyroxenes are also of frequent occurrence in metamorphic rocks, for example, in crystalline limestones, being then of secondary origin.
		day the name pyroxene is used as a group name for all the minerals enumerated below, though sometimes it is also applied as a specific name to include the See also:
	encyclopedia.jrank.org /PYR_RAY/PYROXENE.html (560 words)

	Pyroxene (Site not responding. Last check: 2007-10-12)
		The pyroxenes are the most important group of rock-forming ferromagnesian silicates.
		They are a group of minerals that are closely related structurally, in physical properties, and in chemical composition, even though they crystallize in two different systems; orthorhombic and monoclinic.
		The chemical composition of the pyroxenes can be expressed by the general formula (W,X,Y) in which W, X, Y, and Z indicate elements having similar ionic radii and capable of replacing each other within the structure.
	geology.csupomona.edu /alert/mineral/pyroxene.htm (165 words)

	Irishhealth.com - Online Medical Dictionary
		It varies in colour from white to dark green and fl, and includes many varieties differing in colour and composition, as diopside, malacolite, salite, coccolite, augite, etc. They are all silicates of lime and magnesia with sometimes alumina and iron.
		The pyroxene group contains pyroxene proper, also the related orthorhombic species, enstatite, bronzite, hypersthene, and various monoclinic and triclinic species, as rhodonite, etc.
		Fire + a stranger; so called because it was supposed to the be a stranger, or of rare occurrence, in igneous rocks.
	www.irishhealth.com /dictionary.html?query=pyroxene (137 words)

	ANOMALOUS EUCRITES (Site not responding. Last check: 2007-10-12)
		Pomozdino's pyroxene is unusually magnesian (mg# ~ 0.50) compared to that of non-cumulate eucrites (mg# ~ 0.40).
		The composition of Peramiho pyroxenes (mg# ~ 0.40) is not different from that of main group eucrites.
		We do not believe that these pyroxene inclusions were the product of exsolution out of plagioclase [2] but rather suggest that they were captured during plagioclase crystallization.
	www.gps.caltech.edu /~whsu/pub/LPSC27.html (879 words)

	Pyroxene (augite) (Site not responding. Last check: 2007-10-12)
		The diagnostic feature of any pyroxene is two cleavages that intersect at 89° or 91°.
		Unlike the feldspars or hornblende, pyroxenes show mediocre cleavages that are hard to spot.
		These three cleavage fragments illustrate three things: the pyroxene cleavage is not great, the cleavages intersect at about 90° (horizontal and vertical surfaces, here viewed looking down on horizontal surface), and the cleavage surfaces are not splintery or shiny like hornblende.
	www.pitt.edu /AFShome/c/e/cejones/public/html/GeoImages/1Minerals/1IgneousMineralz/Pyroxene.html (190 words)

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