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Physical Properties of Crystalline Infrared Optical Materials
Published in Paul Klocek, Handbook of Infrared Optical Materials, 2017
James Steve Browder, Stanley S. Ballard, Paul Klocek
Notes: Mica is a birefringent material often used for quarter-wave plates. In addition to muscovite, mica also occurs as biotite, phlogopite, and fluorphogopite. Mica has been used for large-aperture wave plates in high-power laser systems. It exhibits dichroism in the infrared.
Formation of Cu–Au porphyry deposits: hydraulic quartz veins, magmatic processes and constraints from chlorine
Published in Australian Journal of Earth Sciences, 2023
G. N. Phillips, J. R. Vearncombe, J. D. Clemens, A. Day, A. F. M. Kisters, B. P. Von der Heyden
Wide alteration haloes surround porphyry deposits, with estimates that some are 10–100 km3 in volume and extend to at least 2 km depth (Kouzmanov & Pokrovski, 2012). Alteration zones are typically referred to in the literature as potassic, sodic–calcic, sericitic and argillic, with a chlorite–sericite zone as well. More distal alteration includes chloritic and propylitic zones. Sillitoe (2010) lists the minerals in different alteration types. Proximal alteration is mapped as potassic—a term that can signify K-feldspar, biotite, muscovite, phlogopite or a mixture of these minerals. Sericitic, argillic, chloritic and propylitic alteration are less intimately associated with ore, and each of these terms can encompass a variety of minerals. Mineral lists are provided in some published descriptions (e.g. Corbett & Leach, 1998; Vry et al., 2010), but the provision of full coexisting mineral assemblages is not the norm.
Vanadium as a critical material: economic geology with emphasis on market and the main deposit types
Published in Applied Earth Science, 2022
George J. Simandl, Suzanne Paradis
The development of the first successful operation extracting vanadium from a given vanadium-rich shale outside of China will require innovation, perseverance, and pioneering spirit. Determining if the vanadium is predominantly contained in phyllosilicates, compound phosphates, vanadium oxysalts, iron oxides, and oxyhydroxides or organic materials is essential before attempting to select the optimal extraction method for any given project and for project ranking according to development potential. Furthermore, the studies by Zheng et al. (2019) suggest that the distinction between shales consists of specific vanadium-bearing phyllosilicates such as dioctahedral mica (e.g. muscovite and illite) and trioctahedral mica (e.g. phlogopite and biotite) will be important, especially in the case of unweathered ores.
Study on Flotability and Surface Oxidation of Sulfide Minerals from the Tailing of an Iron-Copper Mine Using Electron Probe Microanalyzer
Published in Mineral Processing and Extractive Metallurgy Review, 2021
Yahui Zhang, Zhidong Tang, John Shirokoff
Comprehensive mineral composition studies through microscopic identification and X-ray diffraction analysis show that the mineral composition of the raw material is complex. Metal sulfide minerals included are mainly pyrite, chalcopyrite, bornite, covellite, and pyrrhotite. Iron minerals included are magnetite, martite, hematite, limonite, and siderite. Main gangue minerals are biotite, phlogopite, ankerite, and calcite, followed by quartz, feldspar, tremolite, diopside, and actinolite. Other trace minerals include chlorite, apatite, zircon, garnet, gypsum, ilmenite and titanite, etc. The result of X-ray diffraction analysis of the raw material is shown in Figure 1. It can be seen that the characteristic diffraction peaks of sulfide minerals are not found in the spectrum because of their low contents. Table 4 lists the weight percentage of main minerals in the raw material obtained by microscope observation.