Minerals sampling

Under basic conditions, Mn04 can be used as a titrant for the analysis of Mn +, with both the analyte and the titrant ending up as Mn02. fn the analysis of a mineral sample for... 

Bromine is used as an analytical reagent to determine the amount of unsaturation in organic compounds because carbon—carbon double bonds add bromine quantitatively, and for phenols which add bromine in the ortho and para positions. Standard bromine is added in excess and the amount unreacted is deterrnined by an indirect iodine titration. Bromine is also used to oxidize several elements, such as T1(I) to T1(III). Excess bromine is removed by adding phenol. Bromine plus an acid, such as nitric and/or hydrochloric, provides an oxidizing acid mixture usefiil in dissolving metal or mineral samples prior to analysis for sulfur. 

The apparatus has also been made into an x-ray emission electron-microprobe (9.9) by replacing the target with a transparent section of a rock or mineral sample. The spot being excited could be located easily by viewing it through the sample with an optical microscope. 

Table 1.4. Trace elemeni daia for human bone mineral samples (ppm).

In 1894, the Scottish chemist William Ramsay removed nitrogen and oxygen from air through chemical reactions. From the residue, Ramsay Isolated argon, the first noble gas to be discovered. A year after discovering argon, Ramsay obtained an unreactive gas from uranium-containing mineral samples. The gas exhibited the same spectral lines that had been observed in the solar eclipse of 1868. After helium was shown to exist on Earth, this new element was studied and characterized. 

The XRD data and Zn/Cu ratio are also given for a reference aurlchalclte specimen reported In the literature ( ). All d-spaclngs In the mineral and synthetic aurlchalclte matched the literature values within the lattice volume changes (<2%) reported In Table 1. Over 30 XRD peaks were used In the XRD comparisons. The XRD analysis established that the structure of the mineral and synthetic aurlchalclte was essentially Identical. The only distinguishing features were the higher Cu content and the 1.6Z smaller unit cell volume of the mineral sample compared to the synthetic sample. 

ZnO were present after this calcination, see Figures 3a and 3b. The XRD pattern of CuO was not resolved because the CuO reflections overlapped with undecomposed aurichalcite. XRD patterns of the synthetic sample calcined in a similar manner clearly showed the presence of both CuO and ZnO and no evidence for the aurichalcite structure (1 ). The mineral sample was therefore recalcined at a higher temperature of 400°C, after which no traces of aurichalcite were observed, and both the CuO and ZnO reflections were identified as seen in Figure 3c. The higher temperature needed for the complete transformation of mineral aurichalcite to CuO and ZnO, as compared to the synthetic sample, is most likely a result of the larger size and thickness of the mineral platelets. 

Small solid seuaples can be analyzed directly by dynamic headspace sampling using a platinum coil and quartz crucible pyrolyzer and cold trap coupled to an open tubular column (341,369,379). This method has been used primarily for the analysis of mineral samples and of additives, catalysts and byproducts in finished polymers which yield unreliable results using conventional headspace techniques owing to the slow release of the volatiles to the headspace. At the higher temperatures (450-1000 C) available with the pyrolyzer the volatiles are more readily and completely removed from the sample providing for quantitative analysis. 

The blowpipe is a metallic tube with a small nozzle and mouthpiece used to investigate minerals. Air is blown through the nozzle into the flame of a gas burner, causing the mineral sample to be heated to very high temperatures. 

This same technique should be helpful in understanding wetting properties important in the oil industry since wetting is very dependent on mineral surface energies. The use of contact angle hysteresis information may allow a better understanding of the effects of surface heterogeneities of natural mineral samples. The dynamic Wilhelmy plate technique is ideally suited for such experiments ... 

Non-destructive elemental analysis of solid or liquid samples for major and minor constituents. Used in routine analysis of metallurgical and mineral samples. Most suited to the determination of heavy elements in light matrices (e.g. Br or Pb in petroleum). Well suited for on-stream, routine analysis. Electron beam excitation methods valuable in surface studies in combination with electron microscopy. Detection limits generally in the range 10-100 ppm. Relative precision, 5-10%. 

The difference between lillianite and heyrovskyite is in the width of the galenalike slabs. Counting the number of close-packed sulfur planes in each slab gives a stacking sequence of (6, 6) for lillianite and (9, 9) for heyrovskyite. Synthetic and mineral samples contain other members of the series in which the PbS slab regions have other... 

In order to prepare standard mineral mixtures, pyrite (Py), pyrrhotite (Po), chalcopyrite (Cp), sphalerite (Sp), siderite (Sid), dolomite (Dol), calcite (Cal) and quartz (Qz) were acquired as pure mineral samples through a specialized distributor (Minerobec, Canada). These 8 pure minerals were further cleaned under a binocular microscope and separately crushed to reach 95% under 150pm (typical tailings grain size distribution e.g. Aubertin et al. 2002). Each pure mineral powder was characterized thereafter with a series of chemical and mineralogical techniques. More details can be found in Bouzahzah et al. (2008). The relative density of each mineral specimen were measured with an He pycnometer and are... 

With the advent of multiple-collector inductively coupled plasma-source mass spectrometry (MC-ICPMS) it is now possible to measure Mg/ Mg and Mg/ Mg of Mg in solution with a reproducibility of 30 to 60 ppm or better (Galy et al. 2001). What is more, ultraviolet (UV) laser ablation combined with MC-ICPMS permits in situ analysis of Mg-bearing mineral samples with reproducibility of 100 to 200 ppm (Yoimg et al. 2002a). These new analytical capabilities allow mass-dependent fractionations of the isotopes of Mg to be used as tracers in natural systems. 

The other mineral spectra shown are pyroxenes. The bronzite sample studied (Figure 10) is almost a member of the solid-solution series listed in Table V, although small amounts of Al and Ca are present. Consequently, it should be compared with the synthetic members of this series described below. Even in this natural mineral sample there is clear... 

It has been suggested that powder XRD patterns of some mineral samples of LDH minerals show evidence of superlattice reflections [7,113] but there is no clear consensus [100]. It should also be borne is mind that, as discussed in Sect. 3.5, superlattice reflections may be due to anion, rather than cation, ordering although the latter may be an indication of the former. 

Table 11.6 Interfering nuclear reactions during neutron irradiation of mineral samples. Boldface principal reaction for " °Ar/ Ar dating procedure (from Brereton, 1970).

Table 1. Temporal variation in dissolved Zn (ppm) and Pb (ppb) concentrations for sites proximal to near-surfaoe mineralization. Sampling looations distal to the near-surfaoe mineralization were not...

Fig. 4. Marker plots of SI02 wt.% vs Na20, MgO, AI2O3, P2O5, K2O, CaO, TI02, and A/CNK. The symbols are square for host rock, oirole for white pegmatite, triangle for pink pegmatite, diamond for mineralized samples, and star for altered pegmatite.

A mineral is a naturally occurring, crystalline inorganic compound with a specific chemical composition and crystal structure. Minerals are commonly named to honor a person, to indicate the geographic area where the mineral was discovered, or to highlight some distinctive chemical, crystallographic, or physical characteristic of the substance. Each mineral sample has some obvious properties color, shape, texture, and perhaps odor or taste. However, to determine the precise composition and crystal structure necessary to accurately identify the species, one or several of the following techniques must be employed optical, x-ray diffraction, transmission electron microscopy and diffraction, and chemical and spectral analyses. 

In the remainder of this chapter, specific examples of fibrous minerals are presented. The chemical formulas are given as well as the mineral names. A formula is a shorthand notation that describes the elemental composition of the compound plus the specific ion associations, as determined by three-dimensional structure analysis of the species. Because every mineral sample is not completely analyzed, an ideal formula—one that summarizes the chemistry and associations of the ions—is usually presented. 

Table 2.1 Chemical Analyses of Mineral Samples from the Tremol ite (Ca2Mg5Si8022(OH)2-Actinol ite-Ferroactinol ite (Ca2FesSi8022(0H)2 Series in the Amphibole Group...

The trioctahedral micas can be distinguished by x-ray diffraction from the dioctahedral type. The dioctahedral micas characteristically show distortions that are detected as variations in the bond angles of the hexagonal pattern, Fig. 2.12E (Bailey, 1984). Natural mineral samples often exhibit an occupancy of the B site of greater than 2 and less than 3, producing many variations that cannot be detailed here. 

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