Plagioclase thin section Tectosilicates MicROCKScopic


Twinning in Plagioclase; Thin Section in XPL YouTube

Plagioclase. Solid solution series between Na-rich end-member (albite) and Ca-rich end-member (anorthite). Triclinic shape contributes to interesting optical angles. (001) is a perfect cleavage, and (010) is also quite good. (110) is a very poor cleavage and is not usually seen in thin section. Cleavages intersect at about 93-94 o angles.


Thin section microscope photograph of plagioclase phenocrysts and... Download Scientific Diagram

Peace be upon Everyone. In this video, we are going to study Plagioclase Feldspar (Albite) in Thin Section under Microscope and Observe it's color, cleavage,.


Fractured wall rock plagioclase. (a) Thin section scan of wall rock... Download Scientific Diagram

Mineral analyses were targeted to span the full variability of plagioclase zoning in a given thin section, typically using transects. WDS maps were measured on a representative part of 9 selected thin sections using a 20 µm pixel size to map a total area of ≥ 100 mm 2 (≥ 250,000 pixels) with an analysis time of ~ 21 h per sample (10.


Thin section of biotite, amphibole and plagioclase geology

Feldspar classification This diagram shows how feldspar minerals are classified on the basis of their chemical composition. The sequence of minerals along the base of the triangle represents the solid solution series of plagioclase between albite and anorthite Plagioclase Feldspar Chemical Properties Plagioclase Feldspar Physical Properties


Plagioclase thin section Tectosilicates MicROCKScopic

Plagioclase Feldspar (thin section) Type. Mineral. Cleavage. Cleavages intersect at 93 °, usually not observed in thin section. Colour and Pleochroism. Colorless in thin section; Grains may appear cloudy due to alteration. Relief. Low negative or positive relief.


Plagioclase

PPL Plagioclase (polysynthetic twinning) #1 thin section (hFOV 2mm) GET 360° LIVE INTERACTION Plagioclase PPL properties Relief: Low-moderate negative/positive (Albite-Anorthite series) Habit/Form: Plagioclase commonly occurs both as euhedral and anhedral grains.


Plagioclase thin section Tectosilicates MicROCKScopic

Texture of mare basalt 12002. Rounded and speckled phenocrysts of olivine and large elongate phenocryst of clinopyroxene. Groundmass contains intergrown plagioclase, pyroxene and ilmenite. Figure 18. Large melt inclusion trapped in olivine in 12002. The melt inclusion has crystallized to ilmenite and an intergrowth of plagioclase and pyroxene.


Thin section images of the intact samples (PLG plagioclase; CPX... Download Scientific Diagram

Several videos of plagioclase in thin section, showing typical textures and optical characteristics. Supported by Boise State University and the US National Science Foundation. Key.


Plagioclase thin section Tectosilicates MicROCKScopic

Plagioclase is a series of tectosilicate (framework silicate) minerals within the feldspar group. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a continuous solid solution series, more properly known as the plagioclase feldspar series.


Plagioclase thin section Tectosilicates MicROCKScopic

The orientation of plagioclase laths with respect to the thin section surface may also result in different apparent zoning profiles. In several chondrules, rare, fine-scale K-feldspar exsolution lamellae are observed in albite laths (Lewis, 2018).


Thinsection photographs of plagioclasebearing mylonites ETR13 and... Download Scientific Diagram

Name Pronunciation: Plagioclase + Pronunciation Plagioclase Image Images: Plagioclase Albite Comments: Colorless, lustrous blocky albite crystals to 3 cm in size with a thick dusting of micaceous green micro chlorite. Location: Acushnet Quarry, Bristol Co., Massachussetts, USA. Scale: 17 x 15 x 7.5 cm matrix. © Dan Weinrich Images:


Basalt thin section

The feldspar can be plagioclase or alkali feldspar, or both, depending on the kind of rock (Figure 16.1). But there are many varieties of these granitoids, varying mostly because they contain different minor minerals. Micas (biotite and sometimes muscovite), and amphiboles or pyroxenes of various sorts, are commonly present.


Plagioclase thin section Tectosilicates MicROCKScopic

(c) Entire thin sections ϫ ~24 by 35 mm) showing the edge of an MME. Note the larger crystals of biotite at the border. (d) Rounded plagioclase (Plg) in an MME.


Plagioclase thin section Tectosilicates MicROCKScopic

Identification In general, keys to identifying plagioclase are its (lack of) color, its low birefreingence, and its twinning. When untwinned, plagioclase has bland features and may be difficult to identify unambiguously. Important properties · Color - colorless, but may be altered giving it a grainy or grayish appearance in PP light.


Plagioclase thin section Tectosilicates MicROCKScopic

In thin section, plagioclase commonly shows the characteristic albite polysynthetic twinning. This twinning is the most characteristic identifying feature of plagioclase, and makes its identification easy when present.


Plagioclase thin section Tectosilicates MicROCKScopic

Plagioclase: Property: Value: Comments: Formula:. (010) is also quite good. (110) is a very poor cleavage and is not usually seen in thin section. Cleavages intersect at about 93-94 degree angles. The cleavage may not be obvious in thin section; the best examples are often seen along the edge of the slide. Color/Pleochroism:

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