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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: Montmorillonite STx-1 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: STx-1

MINERAL_TYPE: Phyllosilicate

MINERAL: Montmorillonite (Smectite) (Montmorillonite group)

FORMULA: (Na,Ca)0.33(Al,Mg)2Si4O10(OH)2*nH20

FORMULA_HTML: (Na,Ca)0.33(Al,Mg)2Si4O10(OH)2•nH20

COLLECTION_LOCALITY: Gonzales County, Texas

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.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Analysis by Norma Vergo indicates the sample is smectite + trace amounts of quartz, the less than 2µm cut is pure smectite.

END_XRD_ANALYSIS.

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


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 69.6 wt% SiO2
COMPOSITION: TiO2 0.29 wt% TiO2
COMPOSITION: Al2O3 16.3 wt% Al2O3
COMPOSITION: Fe2O3 1.17 wt% Fe2O3
COMPOSITION: FeO 0.04 wt% FeO
COMPOSITION: MnO 0.01 wt% MnO
COMPOSITION: MgO 3.56 wt% MgO
COMPOSITION: CaO 1.73 wt% CaO
COMPOSITION: Na2O 0.33 wt% Na2O
COMPOSITION: K2O 0.15 wt% K2O
COMPOSITION: P2O5 0.03 wt% P2O5
COMPOSITION: F 0.084wt% F
COMPOSITION: CO2 0.16 wt% CO2
COMPOSITION: LOI 7.50 wt% LOI
COMPOSITION: Total 100.87 wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total wt%

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

Analysis by C. V. Clemency, Dept. of Geological Sciences, SUNY at Buffalo, Buffalo NY for the Clay Minerals Society. Fluorine analysis by J. Thomas Jr., Illinois State Geological Survey, Urbana, Ill, and is not included in the total.

Published in: van Olphen, H. and J.J. Fripiat, eds., 1979, Data handbook for clay materials and other non-metallic minerals, Pergamon Press, New York, p128.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

Trace amounts of 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 3202 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 4593 0.2-3.0µm 200 g.s.=


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