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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: Palygorskite CM46 Attapulgite DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: CM46

MINERAL_TYPE: Phyllosilicate

MINERAL: Palygorskite (Attapulgite)

FORMULA: (Mg,Al)2Si4O10(OH)*4H2O

FORMULA_HTML: (Mg,Al)2Si4O10(OH)•4H2O

COLLECTION_LOCALITY: Quincy, Florida

ORIGINAL_DONOR: Clay Mineral Standard from Wards Natural Science Inc.

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Spectrum published in: Clark, R.N., T.V.V. King, M. Klejwa, G. Swayze, and N. Vergo, 1990, High spectral resolution reflectance spectroscopy of minerals: J. Geophys Res. 95, 12653-12680.

Who note the sample is spectrally pure, no smectite bands.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Analysis by Norma Vergo indicates Palygorskite, medium amount of quartz, trace amount of smectite.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: XRF # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 56.0 wt% SiO2
COMPOSITION: TiO2 0.48 wt% TiO2
COMPOSITION: Al2O3 10.6 wt% Al2O3
COMPOSITION: Fe2O3 3.76 wt% Fe2O3
COMPOSITION: MnO less than 0.02 wt% MnO
COMPOSITION: MgO 8.56 wt% MgO
COMPOSITION: CaO 1.35 wt% CaO
COMPOSITION: Na2O less than 0.15 wt% Na2O
COMPOSITION: K2O 0.95 wt% K2O
COMPOSITION: P2O5 0.59 wt% P2O5
COMPOSITION: LOI 17.0 wt% LOI
COMPOSITION: Total 99.46 wt%

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

Analysis by E. Brandt, and J. H. Christie at USGS Branch of Geophysics, Denver

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

90-95 vol% palygorskite
5-10 vol% quartz
trace opaque grains

Bimodal grain size distribution:

population 1 430µm 70 vol%
population 2 30µm 30 vol%

avg. grain size = 176µm

Light grayish white color, quartz grains do not have palygorskite coatings. Trace opaques sparsely spot palygorskite grains. G. Swayze.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2_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: splib04a r 3798 0.2-3.0µm 200 g.s.= 176 µm
LIB_SPECTRA: splib05a r 5315 0.2-3.0µm 200 g.s.=


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