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USGS Spectral Library Version 7 Sample Description

Kokaly, R.F., Clark, R.N., Swayze, G.A., Livo, K.E., Hoefen, T.M., Pearson, N.C., Wise, R.A., Benzel, W.M., Lowers, H.A., Driscoll, R.L., and Klein, A.J., 2017, USGS Spectral Library Version 7: U.S. Geological Survey Data Series 1035, 61 p., https://doi.org/10.3133/ds1035
For more information on the library, see: local link web link

TITLE: Eugsterite GDS140 Syn DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS140

MINERAL_TYPE: 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:

Hydrous 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.

IMAGE_OF_SAMPLE:
Photo of sample

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, EPMA, 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: 1b2b3b4u # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns