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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 SCa-2 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: SCa-2

MINERAL_TYPE: Phyllosilicate

MINERAL: Montmorillonite (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: San Diego County, CA

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


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 52.4 wt% SiO2
COMPOSITION: TiO2 0.32 wt% TiO2
COMPOSITION: Al2O3 15.0 wt% Al2O3
COMPOSITION: Fe2O3 1.75 wt% Fe2O3
COMPOSITION: FeO less than 0.01 wt% FeO
COMPOSITION: MnO 0.16 wt% MnO
COMPOSITION: MgO 6.68 wt% MgO
COMPOSITION: CaO 0.81 wt% CaO
COMPOSITION: Na2O 1.21 wt% Na2O
COMPOSITION: K2O 0.33 wt% K2O
COMPOSITION: P2O5 0.05 wt% P2O5
COMPOSITION: H2O+ 6.78 wt% H2O+
COMPOSITION: H2O- 12.5 wt% H2O-
COMPOSITION: H2O 19.3 wt% H2O
COMPOSITION: LOI 19.5 wt% LOI
COMPOSITION: Total 98.21 wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total wt%

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

XRF Analysis by Branch of Analytical Chemistry, USGS, Denver. Total above includes LOI value rather than H2O values, and does not include value for FeO as it was determined at same time as H2O. Trace analysis was performed and will be added later.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

~1% opaques.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2_3_4_ # SCa-2.a # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1a2_3_4_ # SCa-2.b # 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 3144 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib04a r 3155 0.2-3.0µm 200 g.s.= <2µm
LIB_SPECTRA: splib05a r 4566 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 4580 0.2-3.0µm 200 g.s.=


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