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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: Wxl Kaolinite + others CU00-19A DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: CU00-19A

MIXTURE_TYPE: Intimate

MIXTURE: Wxl kaolinite + smectite + illlite

FORMULA: Al2Si2O5(OH)4 + smectite + (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,H2O]

FORMULA_HTML: Al2Si2O5(OH)4 + smecite + (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,H2O]

COLLECTION_LOCALITY: Eastern Altertion Center, Cuprite, Nevada, USA

ORIGINAL_DONOR: Gregg Swayze

COLLECTION_LATITUDE: N37 32.08' # degrees and decimal minutes (N or S)

COLLECTION_LONGITUDE: W117 11.05' # degrees and decimal minutes (W or E) P> DATUM: NAD27 # coordinate datum

CURRENT_SAMPLE_LOCATION: U.S.G.S. Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: U.S.G.S. Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

This sample contains well-crystallized kaolinite that when mixed with trace amounts of smectite and illite spectrally mimics poorly crystalline kaolinite. The sample was collectd from an altered Tertiary tuff involved in a hydrothermal event about 7.6 Ma.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Clay separate contains wxl kaolinite, smectite (trace), and illite (trace).

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

None

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

The spectrum has absorptions characteristic of poorly crystalline kaolinite. XRD shows only the presence of wxl kaolinite, smectite, and illite. Apparently these components have a combined spectral signature that mimics pxl kaolinite.

See: Swayze, G.A., 1997, The hydrothermal and structural history of the Cuprite Mining District, southwestern Nevada: an integrated geological and geophysical approach: unpublished Ph.D. Dissertation, University of Colorado at Boulder, 399p.

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: splib05a r 8456 0.2-3.0µm 200 g.s.=


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