Identification of Minerals

Identification of minerals is not a trivial question when dealing with natural objects. Luminescent minerals received from different mineralogists, museums and collectors are often not correctly identified. It is a potential source of serious errors, because the presence of a certain luminescence center in one mineral maybe trivial, while its luminescence in another mineral may represent a certain interest. For example, emission of Mn is common in calcite, but its absence in scheelite is an interesting problem. Thus, when you find the band 

Another example is a mineral named nasonite, which was not suspicious because of its luminescent properties, but gave unexpected results after routine LIBS checking (Fig. 9.2a), where the characteristic fines of Pb were absent, while the emission fines of Ca and Na were very strong. The Raman spectrum (Fig. 9.2b) was also different from those of nasonite. Subsequent analyses by EDX and XRD methods revealed that it is a mixture of two minerals prehnite and pectolite. 

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For the identification of mineral fillers in EPs, XRD was compared with various other analytical techniques (Table 8.55). Both IR and XRF allowed identification... 

Schaffer B., Larson K.D., Snyder G.H., Sanchez C.A. Identification of mineral deficiencies associated with mango decline by DRIS. Hort Sci 1988 23 617-619. 

In the geosciences Raman spectroscopy has traditionally been a laboratory tool for structural analysis of minerals. Recent developments in instrumentation make possible the use of Raman spectroscopy as a tool for routine identification of minerals in field situations. The following advantages characterize Raman analysis of minerals no sample preparation in situ real time measurement non-destructive and non-intrusive sampling samples may be transparent or opaque spectra are well resolved and with high information content. 

Raman spectroscopy is a non-destructive technique that is used in cosmochemistry for identification of minerals and to evaluate the bonding and composition of organic molecules. The technique does not require special sample preparation raw rock samples, polished sections, fine-grained powders, and liquids can be analyzed. Raman spectroscopy is the basis for several instruments that are under consideration for upcoming NASA missions. 

Identification of Minerals in Coal. Once the low-temperature mineral matter residue has been obtained by radiofrequency ashing, the minerals can be identified, and their concentrations can be determined by a variety of instrumental techniques. The best developed, most inclusive, and probably most reliable method used thus far in distinguishing minerals in coal is x-ray diffraction analysis. It has been used extensively by Gluskoter (15), Wolfe (17), O Gorman and Walker (2), and Rao and Gluskoter (1) and has been somewhat successful in quantifying mineral analyses. 

Mohs was first to call attention to the significance of the hardness parameter for identification of minerals, and he provided a sufficiently precise and generally accessible tool for this purpose. The 10-degree, empirical scale of hardness he devised, Figs. 1.1 and 4.1.1 (10—diamond, 9—corun-... 

GRAPHICAL STATISTICAL METHODS OF IDENTIFICATION OF MINERAL AND FATTY OILS, GLASS, SILICONES, AND CATALYSTS... 

Murdoch, A., Zeman, A.J., and Sandilands, R., Identification of mineral particles in fine grained lacustrine sediments with transmission electron microscope and x-ray energy dispersive spectroscopy, J. Sediment. Petrology, 47, 244, 1977. 

A few years after the NAA study, Mainfort worked with James Stoltman using another technique to reexamine the question of pottery import at Pinson Mounds. Stoltman used ceramic petrography to study the physical composition of the sherds. Ceramic petrography involves the identification of minerals in the temper of the pottery and the measurement of the matrix of the sherd in terms of particle size. The percentages of silt-size inclusions plus the type, size, and percentage of mineral inclusions of sand size and larger were determined to characterize each sherd. This is very different information from the chemical composition recorded in NAA studies. The two approaches characterize ceramic compositions in distinctly different ways -one in terms of chemical elements, the other in terms of minerals and rocks - and are generally believed to provide complementary information. 

X-ray phase analysis is used for identification of mineral phases of rocks, soils, clays, or mineral industrial material. The phase analysis of clays is particularly difficult because these materials generally consist of a mixture of different phases, like mixed and individual clay minerals, and associated minerals, such as calcite and quartz. Placon and Drits proposed an expert system for the identification of clays based on x-ray diffraction (XRD) data [45]. This expert system is capable of identifying associated minerals, individual clay minerals, and mixed-layer minerals. It can further approximate structural characterization of the mixed-layer minerals and can perform a structural determination of the mixed-layer minerals by comparison of experimental x-ray diffraction patterns with calculated patterns for different models. The phase analysis is based on the comparison of XRD patterns recorded for three states of the sample dried at room temperature, dried at 350°C, and solvated with ethylene glycol. 

X-Ray Phase Analysis an analytical technique for identification of mineral phases in rocks, soils, clays, or mineral industrial material based on XRD. 

Identification of Minerals induced by Matrix Vesicles Supplemented with Ca and Pi... 

Microscopic Identification of Minerals" - Heinrich, E.W. (ed) Macgraw Hill Book Company, USA (1965). 

One source of the difficulty may arise from the incorrect identification of mineral specimens whose x-ray patterns were used as standards for comparison. X-ray powder patterns of materials used in structure determinations would be of great help in clarifying the problem of identifying these zeolites. An alternative to the actual powder patterns is the calculation of powder patterns from structure data, as demonstrated by Smith (9). 

Although X-ray diffraction or analysis of the X-rays emitted by electron microscopy are the preferred methods of identification of minerals, fast and relatively secure identifications can be made by using chemical reactions. Precipitation reactions and acid-base reactions are two of the most common types of reactions used in chemical identifications. 

The study of clays and minerals played an important role in the development of DTA as an investigative technique. In some instances DTA and DSC provide one of the few routes to the identification of minerals. An ingenious method, elegant in its simplicity, whereby the identity of a component in a mixture can be confirmed is to add the suspected mineral to the reference crucible and repeat the thermal analysis experiment. The relevant peaks should show a diminution in size. 

With the recent increased availability of Fourier transform spectrometers for routine laboratory use, there is great potential for infrared spectroscopy to become more widely used, both for the rapid identification of minerals and for more detailed structural studies. Despite being an established analytical technique, mineralogical infrared spectroscopy has been handicapped by a lack of high-quality reference spectra. There is currently no infrared equivalent of the JCPDS Mineral Powder Diffraction File and many new mineral descriptions still lack infrared spectra. Several compilations of mineral spectra are available but are far from comprehensive and are of variable reliability. Published mineral spectra are scattered throughout numerous journals and are often poorly reproduced with limited frequency ranges. 

Heinrich, E.W., Microscopic Identification of Minerals, McGraw-Hill, New York, 1965,414 pp. 

Jones, M.P Fleming, M.G. (1965) Identification of Mineral Grains. A Systematic Approach to the Determination of Minerals for Mineral Processing Engineers and Students. Elsevier Publishing Co., Amsterdam, New York. 

The simplest method is optical microscopy, in which visible light (photons) is used to observe a sample. It has a resolution limit around 0.25-0.5 pm, which is on the order of 2/2, where 2 is the wavelength of incident light. From a strict colloid science point of view, it lies near the upper limit of colloid particle sizes and appears to be of limited utility. However, it is of great help in the identification of minerals, because it allows observation of crystal habits (the shape and size of crystals, which are determined by their internal symmetry). With experience, many minerals can be identified in a soil sample under a microscope, even from simple inspection. A unique feature of optical microscopy is the availability of polarized light, which is handy in distinguishing minerals or even different crystal types of the same compound (Bullock et al. 1985 Cady, Wilding, and Drees 2010). 

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