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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: Carbon_Black GDS68 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS68

MINERAL_TYPE: Element

MINERAL: Carbon

FORMULA: C

FORMULA_HTML: C

COLLECTION_LOCALITY: Synthetic

ORIGINAL_DONOR: Sargent Welch

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

The sample and the visible-NIR spectrum was originally published in:

Clark, R.N., 1983, Spectral Properties of Mixtures of Montmorillonite and Dark Carbon Grains: Implications for Remote Sensing Minerals Containing Chemically and Physically Adsorbed Water: J. Geophys. Res., v. 88, p. 10635-10644.

The sample was manufactured by Sargent Welch (in about 1980) and consists of 99.0 wt% pure carbon, 0.5 wt% ash, and 0.5 wt% acetone extractable's. The sample was examined with scanning electron microscopy (SEM) and the grain size is quite uniform at 0.17 µm. Note that the Clark 1983 spectrum has too high a reflectance due to scattered light in the UH spectrometer.

IMAGE_OF_SAMPLE:
Photo of sample

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Not Available

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: Other # XRF, EPMA, ICP(Trace), WChem

COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: C: 99.0 wt% C
COMPOSITION: volatile: 0.5 wt% volatile
COMPOSITION: unknown: 0.5 wt% unknown
COMPOSITION: Total 100.0 wt%

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

The sample analysis was by Sargent Welch and consists of 99.0 wt% pure carbon, 0.5 wt% ash, and 0.5 wt% acetone extractable's.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

SEM shows the grains to be spherical with a 0.17 µm diameter. No visible contamination under x-polarized light. Clumps range in size greater than 0.17µm.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns