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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: Goethite Phyllite CU91-236A DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: CU91-236A

MIXTURE_TYPE: Intimate

MIXTURE: Goethite + other mineral phases

FORMULA: alpha-Fe3+O(OH)

FORMULA_HTML: alpha-Fe3+O(OH)

COLLECTION_LOCALITY: Western Alteration Center, Cuprite, Nevada, USA

ORIGINAL_DONOR: Gregg Swayze

COLLECTION_LATITUDE: N37 32.53' # degrees and decimal minutes (N or S)

COLLECTION_LONGITUDE: W117 13.40' # degrees and decimal minutes (W or E)

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 consists of goethite rich altered lower Cambrian Harkless phyllite involved in hydothermal alteration about 7.5 Ma in the now relict western center hydrothermal center at Cuprite, NV. The sample was collected in the central part of the western center along its western margin.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Goethite, kaolinite, and quartz.

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 goethite. There is a broad Fe band at 0.9770 microns. Kaolinite is evident from doublets near 1.4 and 2.2 microns.

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history of the Cuprite Mining District, southwestern Nevada: an integrated geological and geophysical approach: unpublished Ph.D. Dissertation, University of Colorado at Boulder, 399p.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 8179 0.2-3.0µm 200 g.s.=


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