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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.
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