Petrographic characterization

England, B.M. Mikka, R.A. Bagnall, B.J. Petrographic Characterization of Coal Using Automatic Image Analysis, J. Microscopy. 1979, 116, 329-336. 

Petrographic characterization of propylitic alteration associated with porphyry Cu-Mo deposits in the Collahuasi District, Northern Chile implications for mineral exploration... 

Characterization. Ceramic bodies are characterized by density, mass, and physical dimensions. Other common techniques employed in characterizing include x-ray diffraction (XRD) and electron or petrographic microscopy to determine crystal species, stmcture, and size (100). Microscopy (qv) can be used to determine chemical constitution, crystal morphology, and pore size and morphology as well. Mercury porosknetry and gas adsorption are used to characterize pore size, pore size distribution, and surface area (100). A variety of techniques can be employed to characterize bulk chemical composition and the physical characteristics of a powder (100,101). 

During the summer of 2006, 200 petrographic and lithogeochemical samples were collected from the rocks that host the Boomerang massive sulfide deposit. In order to characterize the different rock types sampled ICP-AES and XRF analysis of these samples was completed by ALS Chemex (Sudbury Ontario), and Memorial University of Newfoundland, respectively. 

Eusden, J. D., Gallagher, L. et al. 2002. Petrographic and spectroscopic characterization of phosphate-stabilized mine tailings from Leadville, Colorado. Waste Management, 22, 117-135. 

Petrographic Studies. Polished thin sections were examined by optical methods to determine original mineralogy and alteration phases. The sections were taken and oriented in such a manner to allow comparison of the microscopic mineralogy with the results of the autoradiography experiments The shale was too fine-grained to be characterized in detail. 

At the same time, it is perhaps not unreasonable to ask coal petrographers to refrain from undue criticism unless they are prepared to help us select, separate, and characterize suitable materials for chemical research. 

The following section focuses on the variability of the clay bodies or pastes of the glazed ceramics previously characterized by LA-ICP-MS and LA-TOF-ICP-MS. The purpose of this study is to compare the variation in the ceramic pastes with the different glaze decorative technologies through time. The variability in the ceramic pastes will be characterized through instrumental neutron activation analysis (INAA) and petrographic analysis. 

The most recent petrographic method used to characterize coal macerals is quantitative fluorescence analysis. In this method the macerals are excited by incident ultraviolet light and the spectrum of the resulting fluorescent light is used to characterize the macerals. This technique has led to the discovery of new macerals (18), the quantitative discrimination between certain macerals in a given coal (19), and the correlation of the fluorescence properties of macerals to the rank, and technological properties of coal (20-22). 

Although the characterization of coal macerals on the basis of their fluorescence spectra is a recent innovation, it has already proven to be an excellent fingerprinting tool for the various macerals. In some cases, it is even more sensitive than normal petrographic analysis. The initial results of fluorescence spectral studies show that the various fluorescent macerals in single coals can be statistically discriminated on the basis of their spectral parameters and that even varieties of a single maceral type can be distinguished. Although the spectra obtained at this time are rather broad and not suitable for chemical structure analysis, the potential for structural analysis exists and may be realized with improvements in instrumentation. 

Part of this data in Table II is a series of British maceral concentrates. The Woolley Wheatly Lime sample is 93% fusinite while the Teversal Dunsil concentrate is 80% semifusinite with 13% fusinite. The Aldwarke Silkstone sample contains 43% semifu-sinite and 43% fusinite. The petrographic analysis of PSOC-2 reveals nearly equivalent amounts of fusinite, semifusinite, micrinite, and macrinite (6.8, 8.1, 7.5 and 8.5% respectively in the whole coal) while PSOC-858 contains primarily semifusinite as the inertinite. The differences in faH values for these iner-tinite samples are greater than the experimental error and these differences suggest that NMR techniques may be useful in characterizing the chemical structural differences between inertinite macerals. 

Neutron activation and petrographic analysis of late medieval Spanish pottery from the major Spanish production centers of Seville, Granada, Patema-Manises, Barcelona, and Talavera-Puente allowed progress to be made in uniquely characterizing these production centers (5-7). Efforts to identify different Mexican majolica productions petrographically have been unsuccessful, and an attempt at chemical characterization by directly coupled plasma-optical emission spectroscopy was later determined to have been flawed by problems encountered with the dissolution of the ceramic samples... 

Mittlefehldt D. W. (1979) Petrographic and chemical characterization of igneous lithic clasts from mesosiderites and howardites and comparison with eucrites and diogenites. Geochim. Cosmochim. Acta 3, 1917-1935. 

Swindle T. D., Caffee M. W., Hohenberg C. M., Lindstrom M. M., and Taylor G. J. (1991) Iodine-xenon smdies of petrographically and chemically characterized Chainpur chondrules. Geochim. Cosmochim. Acta 55, 861-880. 

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