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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: Illite IMt-1 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: IMt-1

MINERAL_TYPE: Phyllosilicate

MINERAL: Illite, a group of hydrated mica-clay minerals

FORMULA: (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,H2O]

FORMULA_HTML: (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,H2O]

COLLECTION_LOCALITY: Silver Hill, Montana

ORIGINAL_DONOR: Clay Mineral Society Source Clay Mineral Repository

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

A spectrum of 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. Samples measured for the library include bulk (a) and less than 2µm fraction (b).

The spectrum from 2.5 to 25µm for this sample 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 that the bulk sample is illite + quartz, less than 2µm separate is pure illite/smectite with 95% illite layers.

END_XRD_ANALYSIS.

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


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 52.10 wt% SiO2
COMPOSITION: TiO2 0.79 wt% TiO2
COMPOSITION: Al2O3 21.90 wt% Al2O3
COMPOSITION: Fe2O3 6.44 wt% Fe2O3
COMPOSITION: MnO less than 0.02 wt% MnO
COMPOSITION: MgO 2.39 wt% MgO
COMPOSITION: CaO 1.07 wt% CaO
COMPOSITION: Na2O 0.30 wt% Na2O
COMPOSITION: K2O 7.84 wt% K2O
COMPOSITION: P2O5 0.10 wt% P2O5
COMPOSITION: LOI 6.91 wt% LOI
COMPOSITION: Total 99.56 wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total wt%

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

EM analysis by Gregg A. Swayze, Branch of Geophysics, USGS, Denver.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Note: the Illite IMt-1.a is all grain sizes and thus has spectral purity b in the UV-NIR, while sample Illite IMt-1.b, the <2um fraction removed the quartz and made the spectral purity an a

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2_3_4_ # all grain sizes IMt-1.a # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1a2_3_4_ # less than 2um fraction IMt-1.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 2362 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib04a r 2373 0.2-3.0µm 200 g.s.= less then 2µm
LIB_SPECTRA: splib05a r 3576 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 3589 0.2-3.0µm 200 g.s.=


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