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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Coated_Steel_Girder WTC01-8 DESCRIPT

DOCUMENTATION_FORMAT: Man Made

SAMPLE_ID: WTC01-8

MATERIAL_TYPE: Fireproof coating from steel girder

MATERIAL: Fireproof coating

MINERAL_TYPE: Chrysotile asbestos present up to 20 wt% in sample

MINERAL: Chrysotile asbestos plus other minerals

FORMULA: Not Available

FORMULA_HTML: Not Available

COLLECTION_LOCALITY: Debris pile west of World Trade Center Tower 1

ORIGINAL_DONOR: Gregg Swayze and Todd Hoefen

CURRENT_SAMPLE_LOCATION: U.S. Geological Survey, Denver, Colorado

ULTIMATE_SAMPLE_LOCATION: U.S. Geological Survey, Denver, Colorado

SAMPLE_DESCRIPTION: Fireproof coating from steel girder

Sample WTC01-8 was taken from a coating on a steel girder removed from the debris pile west of WTC tower 1. This sample was collected Sept. 18th. The coating was very distinct having a different color and texture than the surrounding dust. A location map and details of the sample collection process are given in Roger N. Clark et al., Environmental Studies of the World Trade Center area after the September 11, 2001 attack, U.S. Geological Survey Open File Report OFR-01-0429. This report is available at http://pubs.usgs.gov/of/2001/ofr-01-0429/

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

calcite (minor), chrysotile (minor), gypsum (minor), talc (trace), anhydrite (trace), microcline (trace), rozenite (trace) In general minor = 5 - 20 wt%, trace > 5 wt%

see: Roger N. Clark et al., Environmental Studies of the World Trade Center area after the September 11, 2001 attack, U.S. Geological Survey Open File Report OFR-01-0429. This report is available at http://pubs.usgs.gov/of/2001/ofr-01-0429/

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Most notable in its spectrum are absorptions at 1.385 and 2.323 microns which match in position and overall shape those of chrysotile (RS Figure 3). Chrysotile is one of three serpentine minerals and the only one to form with an asbestiform crystal habit. XRD analysis and the depth of these spectral absorptions is consistent with chrysotile forming up to 20 wt% of this coating material. The position of the 2.323 micron absorption in WTC01-8 is consistent with that of chrysotile but the band width is somewhat wider possibly indicating the presence of overlapping 2.307 and 2.343 micron absorptions from dust suppressant oil.

See Roger N. Clark et al., Environmental Studies of the World Trade Center area after the September 11, 2001 attack, U.S. Geological Survey Open File Report OFR-01-0429. This report is available at http://pubs.usgs.gov/of/2001/ofr-01-0429/

END_SPECTROSCOPIC_DISCUSSION.

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

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib05a r 9819 0.2-3.0µm 200 g.s.=


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