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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: Corrensite CorWa-1 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: Cor-Wa-1

MINERAL_TYPE: Phyllosilicate

MINERAL: Corrensite (Chlorite + Vermiculite) (Chlorite group)

FORMULA: 1:1 interstrat. trioct. chlorite & vermiculite (Mg,Fe)6(Si,Al)4O10(OH)8 + (Mg,Fe+2,Al)3(Al,Si)4O10(OH)2*4H2O

FORMULA_HTML: 1:1 interstrat. trioct. chlorite & vermiculite (Mg,Fe)6(Si,Al)4O10(OH)8 + (Mg,Fe+2,Al)3(Al,Si)4O10(OH)2•4H2O

COLLECTION_LOCALITY: Packwood, Washington

ORIGINAL_DONOR: Clay Mineral Society

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Interstratified trioctahedral phyllosilicate. Regularly interstratified chlorite and vermiculite.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Corrensite + albite + quartz, albite ~8 vol. %, quartz ~4%, corrensite coats albite and quartz grains.

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. 12653-12680.

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

Corrensite is a regular 1:1 interstratification of trioctahedral chlorite and trioctahedral smectite or vermiculite.

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. 12653-12680.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

mode:
88 vol% corrensite
8 vol% albite
4 vol% quartz

Corrensite coats albite and quartz grains and occurs as discrete 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 1271 0.2-3.0µm 200 g.s.= 37 µm
LIB_SPECTRA: splib05a r 2237 0.2-3.0µm 200 g.s.= 37 µm


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