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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: Alun0.3+Musc0.4+Pyro0.3 AMX1 DESCRIPT

DOCUMENTATION_FORMAT: Mixture

SAMPLE_ID: AMX1

MIXTURE_TYPE: Areal

MIXTURE: Alun. 30% + Musc 40% +Pyroph 30%

FORMULA: KAl3(SO4)2(OH)6 + KAl2[AlSi3O10](OH,F)2 + Al2Si4O10(OH)2

FORMULA_HTML: KAl3(SO4)2(OH)6 + KAl2[AlSi3O10](OH,F)2 +
Al2Si4O10(OH)2

COLLECTION_LOCALITY: Constructed from other spectra

ORIGINAL_DONOR: Gregg Swayze

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

See alunite_res9, muscovite_gds113, pyrophyllite_pys1a.html

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

See alunite_res9, muscovite_gds113, pyrophyllite_pys1a.html

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE:

See alunite_res9, muscovite_gds113, pyrophyllite_pys1a.html

COMPOSITION_DISCUSSION:

See alunite_res9, muscovite_gds113, pyrophyllite_pys1a.html

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

See alunite_res9, muscovite_gds113, pyrophyllite_pys1a.html

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

See alunite.res9, muscovite.gds113, pyrophyllite.pys1a.html

END_SPECTROSCOPIC_DISCUSSION.

Spectrum has very complex 1.4 and 2-2.5 micron region with superimposed absorptions from all three minerals. The 2.17 micron band typical of alunite has a sharp 2.165 micron band from pyrophyllite. Spectral features of muscovite in this region and at 1.4 microns are dominated by those of alunite and pyrophyllite.

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 7177 0.2-3.0µm 200 g.s.=


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