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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Nontronite NG-1 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: NG-1

MINERAL_TYPE: Phyllosilicate

MINERAL: Nontronite (Fe-bearing Smectite) (Montmorillonite group)

FORMULA: Na0.33(Fe+3)2(Si,Al)4O10*nH20

FORMULA_HTML: Na0.33Fe+32(Si,Al)4O10•nH2O

COLLECTION_LOCALITY: Holen Hagen, Germany

ORIGINAL_DONOR: Clay Mineral Society

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

A spectrum for this sample was published by:

Clark, R.N., T.V.V. King, M. Klejwa, G. Swayze, and N. Vergo, 1990, High spectral resolution reflectance spectroscopy of minerals: J. Geophys Res. 12653-12680.

who noted that it was spectrally pure.

The spectrum from 2.5-25µm was published in: Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.

Two spectra for this sample are in the library, (a) - bulk, and (b) - less than 2µm.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Analysis by Norma Vergo indicates the sample is nontronite + quartz + other; the less than 2µm cut was nontronite + trace quartz.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: XRF # XRF, EM(WDS), ICP(Trace), WChem


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 80.0 wt% SiO2
COMPOSITION: TiO2 0.05 wt% TiO2
COMPOSITION: Al2O3 2.00 wt% Al2O3
COMPOSITION: Fe2O3 11.1 wt% Fe2O3
COMPOSITION: MnO less than 0.02 wt% MnO
COMPOSITION: MgO 0.42 wt% MgO
COMPOSITION: CaO 0.56 wt% CaO
COMPOSITION: Na2O less than 0.15 wt% Na2O
COMPOSITION: K2O 0.72 wt% K2O
COMPOSITION: P2O5 less than 0.05 wt% P2O5
COMPOSITION: LOI 5.28 wt% LOI
COMPOSITION: Total 100.35 wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total 100.35 wt%

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

XRF Analysis by Branch of Analytical Chemistry, USGS, Denver.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

50% quartz
1-2% opaques
no HCl fizz.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib04a r 3494 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib04a r 3505 0.2-3.0µm 200 g.s.= less than 2 µm
LIB_SPECTRA: splib05a r 4962 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 4975 0.2-3.0µm 200 g.s.=


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