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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: Margarite GDS106 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS106

MINERAL_TYPE: Phyllosilicate

MINERAL: Margarite (Mica group)

FORMULA: CaAl2(Al2Si2)O10(OH)2

FORMULA_HTML: CaAl2(Al2Si2)O10(OH)2

COLLECTION_LOCALITY: Chester, MA

ORIGINAL_DONOR: Jim Crowley, USGS Reston

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

40 kV - 30 mA, 6.5-9.5 keV

References: JCPDS #18-276; Huebner's patterns for margarite and chlorite; "ripidolite" GDS157

Found: Margarite and chlorite in subequal proportions Comment: Both phases have sharp reflections indicating good crystallinity and compositional homogeneity. (Jim Crowley, 1993, written communication.)

END_XRD_ANALYSIS.

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

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Possible chlorite absorptions in the 2.3 micron region with a broad absorption from 0.5 to 2.0 microns.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1c2_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 2905 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 4278 0.2-3.0µm 200 g.s.=


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