|
|
(For further information on spectroscopy, see:
http://speclab.cr.usgs.gov)
TITLE: Buddingtonite+Na-Mont CU93-260B DESCRIPT
DOCUMENTATION_FORMAT: MIXTURE
SAMPLE_ID: CU93-260B
MIXTURE_TYPE: Intimate
MIXTURE: Buddingtonite (Feldspar group)+ Na-Mont
FORMULA: (NH4)AlSi3O8*0.5H20
FORMULA_HTML: (NH4)AlSi3O8•½H20
COLLECTION_LOCALITY: Cuprite, Nevada, USA
ORIGINAL_DONOR: Gregg Swayze
COLLECTION_LATITUDE: N37deg 32.583' # degrees and decimal minutes (N or S)
COLLECTION_LONGITUDE: W117deg 11.167' # degrees and decimal minutes (W or E)
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:
Sample is from the western margin of the eastern relict hydrothermal system exposed 0.5 km east of U.S. Highway 95. Acid-sulfate alteration has altered this sample of a rhyolitic volcanic tuff converting what was once feldspar into buddingtonite, montmorillonite, and quartz. This sample was collected from a small hill that has come to be known as "Buddingtonite Bump." Buddingtonite is a NH4-feldspar.
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
Buddingtonite in solid-solution with K-feldspar, also quartz (analysis by Steve Sutley) Montmorillonite was not detected by XRD but may be present at levels below XRD's detection limit.
see: Felzer, B. Hauff, P., and Goetz, A.F.H., 19994, Quantitative reflectance spectroscopy of buddingtonite from the Cuprite mining district, Nevada: Journal of Geophysical Research, v.99, no. B2, p. 2887-2895.
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:
The peak in reflectance at 1.4 microns is an artifact. The band at 1.9056 microns is due to H2O. Bands at 2.0158 and 2.1114 microns are due to Buddingtonite, while the band at 2.2063 microns is due to montmorillonite. Samples similar to this have been analyzed by: Felzer, B., Hauff, P., and Goetz, A.F.H, 1994, Quantitative reflectance spectroscopy of buddingtonite from the Cuprite mining district, Nevada: Journal of Geophysical Research, v. 99, no. B2, p. 2887-2895.
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 7524 | 1.3-5.3µm | 200 | g.s.= |
| LIB_SPECTRA: | splib06a r 24428 | g.s.= |