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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: Cedar_Shake GDS361 HiWeather DESCRIPT

DOCUMENTATION_FORMAT: Man_Made

SAMPLE_ID: GDS361

MATERIAL_TYPE: Wood

MATERIAL: Cedar Shake

FORMULA: Unknown

FORMULA_HTML: Unknown

COLLECTION_LOCALITY: Residential roof in Littleton, Colorado

ORIGINAL_DONOR: Gregg Swayze

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Lab

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Lab

SAMPLE_DESCRIPTION:

This is a sample of a highly weathered cedar shake from residential roof, collected in Littleton, Colorado. Shake was exposed to the weather on a roof for about 15 years and is about 15 cm in length and 2 cm in width. This sample doesn't appear to have any moss.

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:

The spectrum was measured on the weathered surface of the shake. The spectrum ramps up from the visible to 1.9 microns. The absorption edge is centered about 1.0 microns. The slight sharp step at 1.0 microns is an instrument artifact caused by measuring a spatially heterogenous surface. Past 1.9 microns the spectrum has absorptions due to water, cellulose, and lignin. There is no spectral evidence for a 0.68 micron absorption attributable to moss like that present in cedar shake sample GDS360. 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