3.4: Silicate Minerals
Members of the pyroxene family have a complex chemical composition that includes iron, magnesium, aluminum, and other elements bonded to polymerized silica tetrahedra. Polymers are chains, sheets, or three-dimensional structures, and are formed by multiple tetrahedra covalently bonded via their corner oxygen atoms. Pyroxenes are commonly found ...
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Mineral Composition, Pore Structure, and …
This paper experimentally studied the changes in mineral composition, pore structure, and mechanical characteristics of pyroxene granite heated to high temperature (from 25 °C to 1200 °C). The results …
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Pyroxene | Mineral Composition, Structure & Uses | Britannica
pyroxene, any of a group of important rock-forming silicate minerals of variable composition, among which calcium-, magnesium-, and iron-rich varieties predominate.
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13.7.3: Single Chain Silicates (Pyroxenes and Pyroxenoids)
Perhaps the most common pyroxene species is augite (Figure 13.36), a dark green to black pyroxene that typifies mafic and some other igneous rocks. A simplified formula for augite is (Na,Ca)(Mg,Fe,Al,Ti)(Si,Al) 2 O 6. The parentheses (from left to right) group elements that occupy the large octahedral site, the smaller octahedral site, and the ...
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Mullite: Crystal Structure and Related Properties
In particular, the characteristic mullite-type structural backbone of parallel chains consisting of edge-sharing MO 6 octahedra and their specific cross-linkage by TO 4 tetrahedra is ... The characteristics of mono-lithic mullite ceramics are influenced by amount, size, and distribution of mullite, and by the occurrence of coexisting
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Silicate Structures, Neso- Cyclo-, and Soro
This group is the basis for the pyroxene group of minerals, like the orthopyroxenes (Mg,Fe)SiO 3 or the clinopyroxenes Ca(Mg,Fe)Si 2 O 6. Inosilicates (Double Chain Silicates) If two chains are linked together so that …
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Amphibole vs Pyroxene: A Tale of Two Rock-Forming Minerals
Jadeite is a pyroxene and nephrite is an amphibole. Both minerals make pretty bangles, beads, and cabochons. They also create small sculptures and a large variety of utility items. The general characteristics and chemical composition of amphiboles and pyroxenes are alike. But amphiboles are technically more complex than pyroxene.
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The Pyroxene Mineral Group
The name pyroxene is derived from the Greek pyro, meaning "fire", and xenos, meaning "stranger", and was given by Haüy to the greenish crystals found in many lavas which he considered to have been accidentally included there. TThe chemical composition of minerals of the pyroxene group can be expressed by the general formula: XYZ 2 O 6
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Igneous rock | Characteristics, Examples, Formation,
Igneous rock, any of various crystalline or glassy rocks formed by the cooling and solidification of magma, which is a hot (600 to 1,300 °C, or 1,100 to 2,400 °F) molten or partially molten rock. Igneous rocks constitute one of the three principal classes of rocks, the others being metamorphic and sedimentary.
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(PDF) Evolution of spinel-pyroxene symplectite in spinel-lherzolites
We examined the textural and geochemical characteristics of spinel–pyroxene symplectites in spinel–lherzolites collected from the lowest, middle, and upper parts (LZ1, MZ, and UZ1, respectively) of the Horoman Peridotite Complex, Japan. The modal ... The symmetrical layered structural unit, consisting of residual and cumulus peridotites ...
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3.1 Silicate Mineral Groups – A Practical Guide to …
These include minerals such as quartz, feldspar, mica, amphibole, pyroxene, olivine, and a variety of clay minerals. The building block of all of these minerals is the silica tetrahedron, a combination of four oxygen atoms and one silicon …
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Model pyroxenes I: Ideal pyroxene topologies
We establish a working definition of "ideal pyroxene" by describing and illustrating the structural features and relation-ships that can be used as building blocks to derive crystal struc-tures for …
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Structural Controls on the Origin and Emplacement of …
However, there is lack of comprehensive models linking mineral system evolution and structural controls of lithium pegmatites. The majority of studies on lithium pegmatites have focused on chemical fractionation and assume that pegmatites have evolved from a parental granitic source, yet problems emerge when the connection between the granitic ...
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Raman study of anorthite, calcium Tschermak's …
CalvAlrsiror), calcium Tschermak's pyroxene (CaTs, cavlAlrvAlsio6), and gehlenite (Geh, calvAllvAlsior), in both crystalline and glassy states, have been measured in the present work. These aluminum-rich compositions were selected because Al3+ ions have diferent structural roles in crystalline phases and because these composi-
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Raman spectroscopic characteristics of Mg-Fe-Ca pyroxenes
Raman spectra of several compositions of (Mg, Fe, Ca)SiO 3 pyroxenes were collected at ambient conditions. More than 10 Raman vibrational modes were observed for these pyroxenes in the wavenumber range between 200 and 1200 cm −1.In general, these pyroxenes are characterized by (1) the Si-O stretching modes above 800 cm −1; (2) the Si-O bending …
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Structural Breakdown of Natural Epidote and Clinozoisite in …
A heat treatment was performed on selected epidote and clinozoisite crystals to establish the nature of any changes in the optical and crystal-chemical properties and to identify a breakdown product using a wide spectrum of analytical methods. Natural samples were heated from 900 to 1200 °C under atmospheric pressure in ambient oxidation conditions for 12 h. …
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Gabbro Rocks: Identification, Characteristics, Pictures, and …
The chemical composition of gabbro rocks is primarily composed of plagioclase feldspar, pyroxene, and olivine minerals. These minerals give gabbro its characteristic dark color and high density. The rock formation of gabbro is closely related to …
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Characterization and comparison of structural and …
Abstract This study reports the use of Raman spectral features to characterize the structural and compositional characteristics of different types of pyroxene from rocks as might be carried out using a portable field spectrometer or by planetary on-surface exploration. Samples studied include lunar rocks, martian meteorites, and terrestrial rocks. The major structural …
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Pyroxene | Common Minerals
Pyroxene minerals are significant components of many intermediate, and most mafic, igneous rocks. They also occur in many medium-to-high grade metamorphic rocks. Only one pyroxene mineral, a sodium-rich pyroxene …
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Pyroxene Group Minerals | Properties, Occurrence …
Pyroxene is a set of essential rock-forming inosilicate minerals discovered in many igneous and metamorphic rocks. Formula is XY (Si,Al)2O6.
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Structure Formation in Cast Spinelide-Pyroxene Glass …
The problem of controlling the level of consumer characteristics of glass-ceramic materials is studied in many homegrown and foreign studies proving that from the material science point of view they are most affected by microstructural morphometric parameters (size, shape of structural components, etc.) [1, 2].However, by using mathematical modeling and …
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Pyroxene
Pyroxene Chemical Formula. The names of the pyroxene minerals are fundamentally based on their chemical composition. The general formula which represents the chemical composition of the pyroxene group is given by XYZ 2 O 6 in which X can be Na +, Ca 2+, Mn 2+, Fe 2+, Mg 2+, Li +, Y can be Mn 2+, Fe 2+, Mg 2+, Fe 3+, Al 3+, Cr 3+, Ti 4+, and Z ...
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1384
compositional and structural characteristics in rocks and soils contributes greatly to understanding the petrologic processes that produced them. Raman ... we analyzed the same spots on zoned pyroxene grains in a polished section by both Raman spectroscopy and electron microprobe analysis (EMPA). These grains cover a broad range of Fe, Mg, and ...
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Geological and geochemical characteristics and genesis of …
The ore-related intrusion of the deposit is the Cishan pyroxene diorite intrusion (also named Baimangshan intrusion in the north part). The pyroxene diorite is dark gray and gray–green with medium coarse grain texture and massive structure (Fig. 3 a), the main minerals are plagioclases (55–70%), pyroxene (5–10%), amphibolite (8–15%), biotite (3–8%), etc. (Fig. …
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Pyroxene Group: Mineral information, data and localities.
Levien L, Prewitt C T (1981) High-pressure structural study of diopside pyroxene American Mineralogist 66 315-323: 1981: 2.36: 293: 0000813: Diopside: Levien L, Prewitt C T (1981) High-pressure structural study of diopside pyroxene American Mineralogist 66 315-323: 1981: 3.52: 293: 0000814: Diopside
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Prediction of Properties of Cast Spinelide-Pyroxene Glass …
Abstract A spherulite-mesh structure model, which allows prediction of functional properties (wear resistance, heat resistance, and dissipative ability), is proposed after studying the structural features of glass-ceramic spinel-pyroxene materials. The parameters of a dendritic geometry of a glass phase and the spherulite index characterizing the parameters of …
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Pyroxene
The size and charge of the cations that occupy the M2 site chiefly determine the structural type of a pyroxene. Large, singly or doubly charged cations give rise to a diopside (monoclinic) …
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Metamorphic alteration, mineral paragenesis and …
Quartz–amphibole–pyroxene gneiss from the island of Akilia, Southwest Greenland has been claimed to contain the earliest traces of life on Earth in the form of biogenic carbonaceous matter encapsulated as inclusions in apatite crystals. ... Taking into account both the petrographic and structural characteristics of the rock, this paper ...
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Complexities in pyroxene compositions derived from …
The range in soil pyroxene compositions is similar to that of the LRMCC pyroxene separates and the additional pyroxene samples given in Figs. 3A and 3B. Fig. 3C also gives relative pyroxene abundances for the LSCC soils, as larger symbols correspond to a higher pyroxene abundance. Mare soils exhibit a greater overall pyroxene abundance, as well ...
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Model pyroxenes I: Ideal pyroxene topologies
structure. Similarly, "pyroxene A OBTA CT" refers to the unique physical structure, while "pyroxene label A OB TA C " refers to the non-unique sequence of letters representing that structure. In an ideal pyroxene, we define the basal faces of the tetra-hedra as the faces parallel to (100). The two anions that are
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