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 Expanded vermiculite ores examined in this study: their sources and amphibole, talc, and/or serpentine impurities.
February 13, 2019

Expanded vermiculite ores examined in this study

Table 1.  Expanded vermiculite ores examined in this study: their sources and amphibole, talc, and/or serpentine impurities.

Notes: XRD = X-ray diffraction analysis of bulk ore samples (B) and sink fractions (S).  SEM-EDS = Scanning Electron Microscope – Energy-Dispersive X-Ray Spectroscopy.  Band Depth Ratio = 1.40/1.42-µm band depth ratio.  The use of "sodic-

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Average EPMA chemical analyses and calculated mineral formulas of selected unexpanded vermiculite ores.
February 13, 2019

Average EPMA chemical analyses and calculated mineral formulas.

Table 2.   Average EPMA chemical analyses and calculated mineral formulas of selected unexpanded vermiculite ores.

Notes: Compositions of bulk samples not individual minerals.  n = number of microprobe spot analyses collected on multiple mica flakes used to calculate the averaged composition of each sample.   ---- = not enough cation Al and/or Mg to assign to this

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Summary of OH-related mid-infrared (MIR) spectral features of unexpanded and expanded vermiculite ores.
February 13, 2019

Summary of OH-related mid-infrared (MIR) spectral features.

Table 5.  Summary of OH-related mid-infrared (MIR) spectral features of unexpanded and expanded vermiculite ores.

Notes: Vibrational positions from spectra of handpicked, ground mica flakes from the unexpanded GDS469 ore sample from Libby, MT; the unexpanded ALB5SA00 ore sample from Palabora, S. Africa; and the expanded vermiculite ores as noted.  Vibrational

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Summary of OH-related near-infrared spectral features of unexpanded and expanded vermiculite ores.
February 13, 2019

Summary of OH-related near-infrared spectral features.

Table 6.  Summary of OH-related near-infrared spectral features of unexpanded and expanded vermiculite ores.

Notes: Vibrational positions from spectra of handpicked, ground mica flakes from the unexpanded GDS469 ore sample from Libby, MT; and the expanded vermiculite ores as noted.  Vibrational assignments from this study.  oa = OH overtone;

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Electron probe microanalysis analyses and resulting formula of an unexpanded VTx-1 Mg-vermiculite sample from Llano, Texas.
February 13, 2019

Electron probe microanalysis analyses and resulting formula.

Table A5.  Electron probe microanalysis analyses and resulting formula of an unexpanded VTx-1 Mg-vermiculite sample from Llano, Texas. 

Notes:

a Microprobe data for all Fe are binned into FeO.

b There are no data on H2O content. 

Reflectance spectra of representative expanded vermiculite ore samples from each of the four major historical sources.
November 6, 2017

Reflectance spectra of representative expanded vermiculite ore samples

Figure 9. Reflectance spectra of representative expanded vermiculite ore samples from each of the four major historical sources.

Distribution of individual 1.40/1.42-μm band-depth-ratio values of expanded Libby vermiculite ore.
November 6, 2017

Distribution of band-depth-ratio values of expanded vermiculite ore.

Figure A9. The distribution of individual 1.40/1.42-μm band-depth-ratio values of expanded Libby vermiculite ore is positively skewed by the presence of coarse-grained elongate amphibole bundle impurities.

Continuum-removed OH stretch overtone and combination absorptions from spectra.
November 6, 2017

Continuum-removed OH stretch overtone and combination absorptions

Figure 10. (a) and (b) show continuum-removed OH stretch overtone and combination absorptions from spectra of handpicked, ground flakes of phlogopite, hydrobiotite, and vermiculite from unexpanded Libby vermiculite ore.

Evaluation of the total surface area of an expanded vermiculite ore sample.
November 6, 2017

Evaluation of the total surface area of expanded vermiculite ore.

Figure A10. Evaluation of the total surface area of an expanded vermiculite ore sample that must be spectrally measured to derive a precise average 1.38/2.32-μm band-depth-ratio value for source determination.

Continuum-removed absorbance spectra of handpicked, ground flakes of phlogopite, hydrobiotite, and vermiculite.
November 6, 2017

Continuum-removed absorbance spectra.

Figure 11. Continuum-removed absorbance spectra of handpicked, ground flakes of phlogopite, hydrobiotite, and vermiculite from unexpanded Libby ore, and of a K+-exchanged split of the vermiculite, showing the OH stretch fundamental absorptions and their deconvolution into symmetrical Gaussians.

Evaluation of the total surface area of an expanded vermiculite ore sample.
November 6, 2017

Evaluation of the total surface area of expanded vermiculite ore.

Figure A12. Evaluation of the total surface area of an expanded vermiculite ore sample that must be spectrally measured to derive a precise average 2.24/2.38-μm band-depth-ratio value for source determination.