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X-Ray Diffraction (XRD) is typically used to determine bulk mineral assemblages in ores and metallurgical products. Modern high-speed detectors allow rapid data collection on large numbers of samples and whole pattern cluster analysis is used to differentiate sample populations. Furthermore, XRD can be used to:
- Determine clay and phyllosilicate mineral assemblages
- Identify carbonate species
- Identify fibrous mineral species
- Quantify respirable quartz on air filters
- Establish the ratio of monoclinic to hexagonal pyrrhotite
A variety of XRD Analysis options are available through the SGS Advanced Mineralogy Network. Contact your nearest SGS Advanced Mineralogy Facility for pricing.
Option 1: Qualitative XRD Analysis
All minerals identified by X-ray diffraction analysis will be reported and grouped into major (>30%), moderate (10-30%), minor (2-10%) and trace (<2%) amounts. Identification and classification of abundance are based on relative peak heights and mineral crystalline structure.
Option 2: Semi-Quantitative XRD Analysis
All minerals identified by X-ray diffraction analysis will be reported and grouped into major (>30%), moderate (10-30%), minor (2-10%) and trace (<2%) amounts. In addition, mineral abundances (in weight %) generated by RIR (or Rietveld) XRD analysis will be reconciled with a whole rock analysis plus the analysis of any other major elements contained in the sample and reported. Whole rock analysis by X-ray fluorescence spectroscopy includes SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, Cr2O3, MnO, TiO2, P2O5, V2O5 and LOI.
Option 3: Clay Speciation XRD Analysis
Clay minerals identified by X-ray diffraction analysis will be reported and grouped into major (>30%), moderate (10-30%), minor (2-10%) and trace (<2%) amounts. Due to the poor crystallinity of clay minerals, separation of the samples with centrifuge followed by a series of procedures (e.g. the addition of ethylene glycol and high temperature heating) is necessary to differentiate between clay species.
Option 4: Semi-Quantitative Clay Speciation XRD Analysis
Clay minerals identified by X-ray diffraction analysis will be reported and grouped into major (>30%), moderate (10-30%), minor (2-10%) and trace (<2%) amounts. Due to the poor crystallinity of clay minerals, separation of the samples with centrifuge followed by a series of procedures (e.g. the addition of ethylene glycol and high temperature heating) is necessary to differentiate between clay species. In addition, mineral abundances for the bulk sample (in weight %) generated by RIR (or Rietveld) XRD analysis will be reconciled with a whole rock analysis plus the analysis of any other major elements contained in the sample and reported. Whole rock analysis by X-ray fluorescence spectroscopy includes SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, Cr2O3, MnO, TiO2, P2O5, V2O5 and LOI.
Option 5: Quantitative XRD Of Free Silica (Alpha Quartz) – Bulk Sample
The percent determination of free silica (as alpha quartz) in a bulk sample will be calculated and reported. Calculation of free silica is based on the comparison of the major quartz peak intensities of the sample with that of a standard LiF mixture.
Option 6: Determination of Respirable Silica (Free Quartz) – Air Filter
The determination of respirable silica (in milligrams) will be calculated and reported. The sample will be received by mineralogy loaded onto a 25 mm, 0.5 µm pore size silver membrane filter. The filter is analyzed over 2 major diffraction peaks (31.04 degrees and 58.95 degrees 2 theta) in order to avoid errors due to peak overlap with other minerals. The calculation for the amount of quartz present is based on the comparison of the normalized peak intensities of the sample with the peak intensities of the sample with the peak intensities of known standards. A standard calibration is measured to ensure quality of instrumentation.
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