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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: Cobalt_blue GDS790 DESCRIPT

DOCUMENTATION_FORMAT: Man_Made

SAMPLE_ID: GDS790

MATERIAL_TYPE: Paint Pigment

MATERIAL: Paint Pigment

FORMULA: CoAl2O4

FORMULA_HTML:CoAl2O4

COLLECTION_LOCALITY: Phillips Collection, Washington, D.C

ORIGINAL_DONOR: Patricia Favero

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Lab

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Lab

SAMPLE_DESCRIPTION:

Dry powdered paint pigment from Kremer Pigments Inc.

Visual examination in sunlight indicates this sample is light blue.

IMAGE_OF_SAMPLE:
Photo of sample

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

This pigment has a broad reflectance peak centered at 0.44 microns with a weak absorption at 0.481 and a stronger broader absorption centered at 0.588 microns. Other broad bands are centered at 1.36 (many overlapping absorptions) and 2.164 microns (continuum removed positions). Positions of absorptions and number of absorptions in absorption complexes with overlapping bands are approximate, and would require spectral deconvolution to determine the actual number and position of absorptions. G. Swayze

END_SPECTROSCOPIC_DISCUSSION.

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