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Clark and others 2007 USGS Data Series 231
Spectral Library splib06a Sample Description

(For further information on spectroscopy, see: http://speclab.cr.usgs.gov)

TITLE: Goethite0.02+Quartz GDS240 DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: GDS240

MIXTURE_TYPE: Intimate

MIXTURE: 2 wt% Goethite and 98 wt% quartz

FORMULA: alpha-FeO(OH) and SiO2

FORMULA_HTML: alpha-FeO(OH) and SiO2

COLLECTION_LOCALITY: Goethite WS222 Superior Mine, Marquette, Michigan, USA

ORIGINAL_DONOR: Ward Science Collection

COLLECTION_LATITUDE: Not Available # degrees and decimal minutes (N or S)

COLLECTION_LONGITUDE: Not Available # degrees and decimal minutes (W or E)

DATUM: Not Available # coordinate datum

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

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

SAMPLE_DESCRIPTION:

Physical mixture of ground 2wt% Goethite WS222 with 98 wt% ground quartz. Quartz from a crystal of quartz with minimal fluid inclusions. Our goal was to unsaturate the Fe-absorptions.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

see: Goethite WS222

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: NONE # XRF, EM(WDS), ICP(Trace),WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

See Goethite WS222

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Spectrum has characteristic goethite absorptions at 0.5000, 0.670, and 0.9574 microns but much weaker than in endmember sample. Bands are unsaturated.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_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 8164 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib06a r 25198 g.s.=