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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: Fe-Hydroxide SU93-106 amorph DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: SU93-106

MIXTURE_TYPE: Intimate

MIXTURE: Secondary Fe-minerals coating a rock

FORMULA: Unknown

FORMULA_HTML: Unknown

COLLECTION_LOCALITY: Alamosa River, Colorado, USA

ORIGINAL_DONOR: Gregg Swayze

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: USGS Spectral Library Denver, Colorado

ULTIMATE_SAMPLE_LOCATION: USGS Spectral Library Denver, Colorado

SAMPLE_DESCRIPTION:

Sample was collected from the Alamosa River downstream from the Summitville mine about 1 year after a catastrophic release of metal-rich mine waste water from the mine. Collected about 15 kilometers downstream from the Mine. Sample is of secondary Fe-minerals coating a river cobble.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

No Secondary Fe-minerals identified.

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

None

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Spectrum shows a strong absorption edge in the visible with a weak absorption at 0.9637 microns. This band position is compatible with goethites and schwertmannite. Lack of a band near 0.65 microns may indicate the sample is possibly schwertmannite or nanocrystalline goethite or both.

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 8140 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib06a r 25174 g.s.=