Biotite Mineral | Uses and Properties
Biotite Mineral Data
WEBBiotite is a group name for phlogopite, siderophyllite and eastonite, with the chemical formula K (Mg,Fe++)3 [AlSi3O10 (OH,F)2. Learn about its environment, origin, crystal structure, physical and optical properties, …
Biotite composition as a tool for the identification of …
Some individual tephra deposits display sequential changes in biotite composition that allow separate phases of the eruption to be identified, greatly increasing the potential precision for correlation. In addition, devitrified lavas that are unsuitable for glass analysis can be correlated to coeval tephra deposits by their biotite compositions.
Biotite Group – WGNHS – UW–Madison
Biotite refers to a group of common rock-forming minerals forming a series between phlogopite and annite. The name is best used as a field name for dark micas for which the exact composition has not been determined. It is found in a variety of occurrences. It occurs in plutonic igneous rocks ranging from granites to gabbronorite to syenites. Large …
Contrasting composition of two biotite generations in the …
Physicochemical parameters estimated by biotite composition suggest that there is a trend of strongly decreasing temperature from the crystallization of generation I to generation II biotite. It is therefore concluded that temperature is a major factor favourable for REE mineralization in the Lizhuang deposit, particularly given related ...
Schist | Properties, Formation, Occurrence and Uses
The composition of schist can vary widely depending on factors such as the parent rock, the degree of metamorphism, and the specific minerals present in the geological environment. ... Biotite is dark-colored, often black or brown, while muscovite is light-colored, often silvery or white. Quartz: Quartz is a common mineral in schist, ...
Granite | Properties, Formation, Composition, Uses
Biotite: Biotite is another dark-colored mineral that is sometimes found in granite, accounting for up to 5% of the rock's composition. It is a type of mica that gives granite a dark, almost black color. There can be variations in the mineral composition of granite depending on the location where it was formed.
Biotite compositions and geochemistry of porphyry-related …
Biotite composition has been used to determine fO 2, and the compositions of halogens in aqueous fluids have been examined related to the ore deposits, such as PCDs (Idrus et al., 2007), intrusion-related gold, and tungsten (Mo, Cu) deposits (Zhang et al., 2016). Commonly, Sn and W ore deposits are associated with the relatively reduced …
Biotite Mica
Biotite and muscovite are aluminum-containing silicates which cleave in thin sheets and are called micas. Biotite is a general field term for dark micas. Biotite has the general …
Biotite mica: The mineral Biotite information and pictures
Biotite is found in abundance worldwide, but collectors specimens are not common and come from few localities. Noteworthy localities include Mabubas, Bengo Province, Angola; Mendig, Eifel Mts, Germany; and Serra da Freita, Arouca, Portugal, where it comes in rounded nodules. In Canada huge "books" and well formed "barrels" come from …
Characterization of biotite and amphibole compositions in …
Composition of biotite. The biotite compositions considered in this study are plotted on a ternary diagram (FeO–Al 2 O 3 –MgO) as 3-D volumes and as contoured …
Biotite
Biotite - K(Mg,Fe 2+) 3 [AlSi 3 O 10 (OH,F) 2 Biotite is a common phyllosilicate mineral within the mica group, with the approximate chemical formula K(Mg,Fe) 3 AlSi 3 O 10 (F,OH) 2.Biotite is a solid solution …
(PDF) Application of Biotite Composition in Determination …
The biotite composition of diorite from the complex has been studied by Dada and Ashano, (2012). They suggested that the diorite are formed from transition between peraluminous and calc-alkaline ...
Biotite
Biotite, also known, as 'black mica' is a rock-forming femic phyllosilicate that occurs in several igneous and metamorphic rocks. The mineral was named in honor of the French scientist Jean-Baptiste Biot, who devoted his life to study the optical properties of the micas. ... Twinning: {001} composition plane – [310] twin axis ...
Syenite : Formation, Composition, Classification, Uses
Biotite Syenite: Biotite syenite contains a notable amount of biotite mica, which is a dark-colored mineral. This type of syenite can have a distinct texture and appearance due to the prevalence of biotite. ... Composition: Monzonite is a rock that falls between syenite and diorite in composition, containing plagioclase feldspar and both …
14 Metamorphism of Pelitic Rocks – Open Petrology
14.16 Composition diagrams and reactions at conditions of the biotite isograd place holder Figure 14.16 shows Thompson projections for conditions equivalent to zones F and J in Figure 14.15. These zones represent conditions in the amphibolite facies that are below, and above, the garnet isograd.
Biotite K(Mg Fe2+ (Al Fe3+)Si O (OH F) 3 10 2
Biotite K(Mg;Fe2+)3(Al;Fe3+)Si3O10(OH;F)2 °c 2001 Mineral Data Publishing, version 1.2 Crystal Data: Monoclinic. Point Group: 2=m: Uncommon in good crystals, tabular or short prismatic, with pseudohexagonal outline, to 3 m. Typically irregular foliated or bent masses; in scaly aggregates or disseminated grains.
3.4 Classification of Igneous Rock
The diagram in Figure 3.4.1 can be used to help classify igneous rocks by their mineral composition. An important feature to note on this diagram is the red line separating the non-ferromagnesian silicates in the lower left (K-feldspar, quartz, and plagioclase feldspar) from the ferromagnesian silicates in the upper right (biotite, amphibole ...
Geochemical characteristics of biotite from felsic intrusive …
Chemical composition of magmatic biotite is sensitive to chemical and physical factors associated with crystallization of the magma (Munoz, J.L., 1992, Abdel-Rahman, A.F.M., 1994) and also to exsolved hydrothermal fluids (Siahcheshm et al., 2012).The interlayer cations (K +, Na +, Ca 2 +, Ba +, and Cs +) in biotite crystals could …
A new activity model for Fe–Mg–Al biotites: II
As a general remark, we use in all applications the activity–composition (a–X) relations for biotite as outlined in part-I with mixing properties given in Table 8 and standard-state thermodynamic properties for annite (Ann), phlogopite (Phl), and eastonite (Eas) given in Table 9 of the companion paper.For alternative versions of our biotite …
4.1: Classification of Igneous Rocks
Igneous rocks are classified based on texture and composition. Texture describes the physical characteristics of the minerals, such as grain size. ... Minor amounts of dark-colored (mafic) minerals like amphibole and biotite mica may be present as well. Felsic igneous rocks are rich in silica (in the 65-75% range, meaning the rock would be 65 ...
Chlorine, titanium and barium-rich biotites: factors …
The composition of biotite reflects the composition of the last fluid in equilibrium with the mineral, i.e. the composition of the fluid immediately before the grain boundaries were fluid-undersaturated. Thus, the variations in biotite composition reflect how the fluid was gradually consumed throughout the shear zone rock.
Biotite as a petrogenetic discriminator: Chemical insights from …
Igneous and metamorphic biotite composition may correspond to differences in whole-rock composition, hydrothermal fluid-rock interaction, co-crystallization with other minerals (e.g., garnet and muscovite), and thermodynamics (P/T) of the rock system.
Mineral chemistry of magmatic and hydrothermal biotites …
The chemical composition of biotite is sensitive to the physicochemical conditions of the host magma and those of exsolved hydrothermal fluids, including temperature, pressure, oxygen fugacity, and composition (Munoz, 1992, Abdel-Rahman, 1994, Webster, 2004, Siahcheshm et al., 2012).
(PDF) Composition of biotite from granitic rocks of the …
Biotite composition suggests partial melting of the metasedimentary protolith as the source of the two-mica granite. The plots of Y vs. SO2, P2O5 vs. SiO2, % normative C vs. Rb, Y vs. Rb, and Th ...
Using magmatic biotite chemistry to differentiate barren and
The geochemistry of biotite crystals from thirty fertile and barren Silurian–Devonian granitoids of New Brunswick, Canada, was studied in situ using electron microprobe and laser ablation inductively coupled plasma-mass spectrometry to investigate the suitability of biotite geochemistry as a diagnostic fertility index among …
Rubidium isotope compositions of biotite in granites record …
Magmatic-hydrothermal processes associated with granitic rocks are crucial for magma evolution and rare metal enrichment. This study presents Rb isotope compositions (δ 87 Rb) for whole rocks and Rb-enriched minerals (biotite and K-feldspar) from the Qitianling granite pluton in South China, which hosts one of the world's largest Sn-ore deposits. . …
Biotite composition as a tracer of fluid evolution and …
Our observations of biotite chemical composition suggest that the formation of different types of biotite at Qulong can be attributed to the influence of host-rock …
Gneiss: Metamorphic Rock
What Is Gneiss? Gneiss is a foliated metamorphic rock identified by its bands and lenses of varying mineral composition. Some of these bands (or lenses) contain granular minerals that are bound together in an interlocking texture.. Other bands contain platy or elongated minerals that show a preferred orientation that parallels the overall banding in the rock.