Sample Description USGS Spectral Library Version 7

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: Thenardite HS450 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS450.1B, HS450.2B, HS450.3B, HS450.4B

MINERAL_TYPE: Sulfate

MINERAL: Thenardite

FORMULA: Na2SO4

FORMULA_HTML: Na₂SO₄

COLLECTION_LOCALITY: Camp Verde, California

ORIGINAL_DONOR: Hunt and Salisbury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

"This sample is transparent in hand specimen and appears unusually pure."

Hunt, G.R., Salisbury, J.W., and Lenhoff, C.J., 1971, Visible and Near-Infrared spectra of minerals and rocks: IV. Sulphides and Sulphates: Modern Geology, V. 3, p 1-14.

Grain size fractions are indicated by the extension after the sample number:
.1B = <5 µm
.2B = <74 µm
.3B = 74-250 µm
.4B = 250-1200 µm
.6 = cut slab

IMAGE_OF_SAMPLE:
NO PHOTO

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

40 kV - 30 mA, 6.5-9.5 keV
Reference : JCPDS #5-631
Found: Thenardite

Comment: One phase observed in routine work. Sharp peaks indicate good crystallinity and compositional homogeneity. A great match with the JCPDS pattern.

J.S. Huebner ,J. Pickrell, T. Schaefer, unpublished data, written communication, USGS, Reston, VA (1994)

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Weak sharp absorptions at 2.31 and 2.39 microns indicate the presence of hydroxyl-bearing impurities in all grain sizes. G. Swayze.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1c2_3_4_ # HS450.1B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2_3_4_ # HS450.2B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2_3_4_ # HS450.3B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2_3_4_ # HS450.4B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns