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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: Kalun+kaol+gth mv2-ar3 DESCRIPT

DOCUMENTATION_FORMAT: Mixture

SAMPLE_ID: MV2-AR3

MIXTURE_TYPE: Intimate

MIXTURE: Alunite + kaolinite + goethite

FORMULA: KAl3(SO4)2(OH)6 + Al2Si4O10(OH)2 + Fe3O(OH)

FORMULA_HTML: KAl3(SO4)2(OH)6 +Al2 Si4O10(OH)2 + Fe3O(OH)

COLLECTION_LOCALITY: Alunite Ridge, near Christmas Mine, Tushar Mountains, Piute County, Utah LAT/LONG: 38 22 46.05 N, 112 19 48.92 W

ORIGINAL_DONOR: Barnaby Rockwell

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

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

SAMPLE_DESCRIPTION:

Hydrothermally altered wall rock immediately adjacent to K alunite veins formed in high temperature magmatic steam environment. Dark reddish argillized appearance.

See: Rockwell, B.W.,2002, Descriptions, spectral plots, and digital reflectance spectra of samples applied to spectral analysis of imaging spectroscopy data: Utah (East Tintic Mountains, Oquirrh Mountains, Wasatch Mountains, and Tushar Mountains), Nevada (Goldfield Hills), and New Mexico (Jemez Mountains), USA, 1999-2002: U.S. Geological Survey Open-File Report 02-407, electionic webpages. (http://pubs.usgs.gov/of/2002/ofr-02-407) END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Major greater than 25%: K alunite Minor 5%-25%: kaolinite Trace less than 5%: quartz, goethite, hematite

see:

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

None

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Spectrum mostly dominated by goethite absorptions in the electronic region (.35-1.35 microns) and alunite in the vibrational region (1.35 2.5 microns). A kaolinite absorption forms a shoulder on short wavelength side of the alunite OH overtone doublet in the 1.4 micron region. Kaolinite absorptions also deepen the 2.17 micron absorption increasing the depth of the 2.201 micron alunite band relative to the main alunite band at 2.17 microns.

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 8396 0.2-3.0µm 200 g.s.=


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