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Petroleum Geological Survey
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Mica is the most common silicate and has a shiny texture. The mica group silicates are layered and sheet-forming materials. All have a monoclinic crystal structure. The mica breaks along the cleavage plane, forming very thin elastic slices. The basic unit is the SiO4– tetrahedral ion. Each tetrahedral ion is linked by three corners to the neighboring tetrahedral forming a sheet structure. The crystal structure of mica is monoclinic. The most common mica silicates are biotite and muscovite. Mica has various colors from white to brown to black. Muscovite produces colorless transparent slices. ‘Biotite’ refers to the dark mica series. The mica group silicates possess a high density range between 2.8 and 3.1 g/cm3. Mica is used as a thermal and electrical insulator.
Minerals, rocks and sediments
Published in Richard J. Chorley, Stanley A. Schumm, David E. Sugden, Geomorphology, 2019
Richard J. Chorley, Stanley A. Schumm, David E. Sugden
(6) Muscovite or white mica (KAl2(AlSi3O10)(OH)2) – a potassium-rich alumina-silicate similar in structure to biotite except that it has more Al+++ ions, instead of the latter’s Fe ++ and Mg ++ ions, giving it a more chemically resistant structure.
Inhalation Toxicology
Published in Ronald Scott, of Industrial Hygiene, 2018
The mineral form of mica is called muscovite. It is found as plates that separate into thin sheets, or as a powdery product. It serves well as a heat or electrical insulator, so it is used in electrical devices and appliances. The ground material is added to roofing, and it has served as a mold release agent in the rubber industry. It infrequently is responsible for pneumoconiosis.
Comparison and evaluation of alumino-silicate samples as a dual source of alumina and potash values
Published in Canadian Metallurgical Quarterly, 2023
The variation in the aluminum extraction from the silicate rocks with milling time is shown in Figure 5c. As expected, the extraction values showed an increasing trend with time which saturated on prolonged milling. The mica and sericite samples yielded better Al extraction (75-80%) than diaspore and feldspar (40-45%). The better response of mica and sericite can be attributed to the amenable muscovite phase contributing a major fraction of aluminum in the feed. Mohr's hardness of the muscovite is 2-2.5, whereas diaspore and microcline have approximately 7 and 5, respectively. The variation in the potassium extraction with milling time is shown in Figure 5d. A similar trend was observed in the samples as aluminum. However, it was observed that the diaspore yielded better extraction values compared to mica and sericite. The maximum potassium extraction of 71% was achieved after 8 h milling in diaspore. The better response of the mica and diaspore samples can be attributed to the amorphization of the muscovite phase, which is the only contributor to potassium values in both samples.
Shaping surfaces and interfaces of 2D materials on mica with intercalating water and ethanol
Published in Molecular Physics, 2021
Abdul Rauf, José D. Cojal González, Alper Balkan, Nikolai Severin, Igor M. Sokolov, Jürgen P. Rabe
Flexible interfaces between a mica substrate and 2D materials exfoliated thereon, are emerging as a model experimental system to investigate structure and properties of thin films of small molecules confined to interfaces [11–16]. Muscovite mica is a naturally occurring hydrophilic layered crystal. It exhibits macroscopically large atomically flat cleavage planes. For this reason, it is widely used as a substrate for imaging single macromolecules or thin molecular films. Furthermore, for its structural and chemical homogeneity, mica has been widely used to investigate properties of liquids when squeezed between its surfaces [15,16]. 2D materials deposited onto a mica surface covered with a molecular liquid film prevent film disruption by a Scanning Force Microscopy (SFM) tip [11]. Furthermore, 2D materials such as graphene and molybdenum disulfide (MoS2) when deposited on a substrate replicate the topography of molecular films and even single molecules residing on the substrate [11,12]. This allows to image the films confined at the mica-2D sheet interfaces with SFM.
Cholesteric dislocations in mica wedges
Published in Liquid Crystals Reviews, 2021
Mica muscovite is a mineral belonging to the class of phyllosilicates made of stacks of layers. In mica muscovite, two layers, intercalated with a sheet of ions, are assembled into two types of triplets labelled T1 or T2. The two layers of each triplet have ‘head-to-tail’ orientations: the apical oxygens of the octahedra belonging to the upper layer are directed downward while those in the lower layer have the upward orientation. The intercalating ions are located in octahedral cavities obtained by a horizontal shift l between the two layers in triplets. The shift (staggering) vectors and in triplets and form the angle of 60.