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(For further information on spectroscopy, see:
http://speclab.cr.usgs.gov)
TITLE: K-Alunite CU98-5C Intermd. Temp? DESCRIPT
DOCUMENTATION_FORMAT: MIXTURE
SAMPLE_ID: CU98-5C
MIXTURE_TYPE: Intimate
MIXTURE: K-alunite + other mineral phases
FORMULA: KAl3(SO4)2(OH)6
FORMULA_HTML: KAl3(SO4)2(OH)6
COLLECTION_LOCALITY: Eastern Alteration Center, Cuprite, Nevada, USA
ORIGINAL_DONOR: Gregg Swayze
COLLECTION_LATITUDE: N37 32.087' # degrees and decimal minutes (N or S)
COLLECTION_LONGITUDE: W117 10.193' # degrees and decimal minutes (W or E) P> 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 was collected from the southeastern portion of the eastern alteration center at Cuprite, NV. The sample was a volcanic rhyolite tuff of Tertiary age prior to hydrothermal alteration about 7.6 Ma.
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
alunite (major), opal-A (major), tridymite (minor), and quartz (trace).
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 alunite. The relatively less intense absorption features may indicate that this alunite formed at intermediate temperatures (less than that of alunite CU91-217G1).
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history of the Cuprite Mining District, southwestern Nevada: an integrated geological and geophysical approach: unpublished Ph.D. Dissertation, University of Colorado at Boulder, 399p.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 7436 | 0.2-3.0µm | 200 | g.s.= |
| LIB_SPECTRA: | splib06a r 24129 | g.s.= |