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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: Eugsterite GDS140 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS140

MINERAL_TYPE: Hydrous Sulfate

MINERAL: Eugsterite

FORMULA: Na4Ca(SO4)3*2H2O

FORMULA_HTML: Na4Ca(SO4)3•2H2O

COLLECTION_LOCALITY: X-rayed (Synthetic)

ORIGINAL_DONOR: Jim Crowley

CURRENT_SAMPLE_LOCATION: USGS Reston, Virginia

ULTIMATE_SAMPLE_LOCATION: USGS Reston, Virginia

SAMPLE_DESCRIPTION:

evaporation of Na2SO4 + CaSO4 solution at 70°C
Spectrum originally published in:
Crowley, J.K., 1991, Visible and Near-Infrared (0.4 - 2.5µm) Reflectance Spectra of Playa Evaporite Minerals: Journal of Geophysical Research, vol 96, no.B10, p. 16,231-16,240.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Sample is eugsterite but contains a small amount of gypsum (Crowley, 1991)

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

evaporation of Na2SO4 + CaSO4 solution at 70°C

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

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: splib04a r 1615 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 2652 0.2-3.0µm 200 g.s.=


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