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USGS Spectral Library Version 7 Sample Description

Kokaly, R.F., Clark, R.N., Swayze, G.A., Livo, K.E., Hoefen, T.M., Pearson, N.C., Wise, R.A., Benzel, W.M., Lowers, H.A., Driscoll, R.L., and Klein, A.J., 2017, USGS Spectral Library Version 7: U.S. Geological Survey Data Series 1035, 61 p., https://doi.org/10.3133/ds1035
For more information on the library, see: local link web link

TITLE: Beidellite_montmor_GDS123 DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: GDS123

MIXTURE_TYPE: Intimate

MIXTURE: Beidellite + Montmorillonite

FORMULA: (Na,Ca,0.5)0.3 Al2(Si,Al)4O10(OH)2*nH2O

FORMULA_HTML: (Na,Ca0.5)0.3Al2 (Si,Al)4O10(OH)2 *nH2O

COLLECTION_LOCALITY: Blackjack Mine, Florida Mountain, Idaho

ORIGINAL_DONOR: Jim Post

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Based on XRD sample is a mixture of montmorillonite and beidellite.

IMAGE_OF_SAMPLE: NONE
END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Montmorillonite (Major), Beidellite (Major), S. Sutley.

Beidellite plus another phase. XRD identification of beidellite confirmed with the Greene-Kelly test. B. Benzel.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

avg. grain size =

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION: The spectrum of this sample shows a relatively broad combination absorption centered at 2.19 microns. When compared to the spectrum of spectral library Beidellite+montmorillonite sample GDS124, the greater fwhm of this sample's 2.19 micron absorption is compatible with the presence of minor to major amounts of montmorillonite. G. Swayze.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2b3b4b # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns