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Clark and others 2007 USGS Data Series 231
Spectral Library splib06a Sample Description

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

TITLE: Chlorite + Calcite GDS315 - GDS316 DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: GDS315

MIXTURE_TYPE: Intimate

MIXTURE: Chlorite + Calcite

FORMULA: CaCO3 and (Mg,Fe)3(Si,Al)4O10(OH)2-(Mg,Fe)3(OH)6

FORMULA_HTML: CaCO3+Ca2(Al,Fe+3)3(SiO4)3(OH) and (MgFe)3(SiAl)4O10(OH)2
-(MgFe)3(OH)6

COLLECTION_LOCALITY: Calcite from Mexico and Chlorite from Flagstaff Hill
California. For further information pertaining to this sample see:

ORIGINAL_DONOR: Purchased Egger's lapidary

COLLECTION_LATITUDE: Not Available # degrees and decimal minutes (N or S)

COLLECTION_LONGITUDE: Not Available # degrees and decimal minutes (W or E)

DATUM: Not Available # coordinate datum

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Samples constructed from ground and sieved pure minerals GDS157 (chlorite), and GDS298 (calcite) in variable proportions.
33wt% Chlorite + 67wt% Calcite GDS315
67wt% Chlorite + 33wt% Calcite GDS316

For further information pertaining to this sample see: Dalton, B.J., Bove, D., Mladnich, C., Clark, R.N., Rockwell, B., Swayze, G.A., King, T., Church, S., Spectral Classification Of Similar Materials Using the Tetracorder Algorithm: the Calcite-Epidote-Chlorite Problem, Proceedings of the Tenth JPL Airborne Earth Science Workshop, Jet Propulsion Laboratory Publication 02-1, pp.93-101.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Samples were identified as pure.

For further information pertaining to this sample see: Dalton, B.J., Bove, D., Mladnich, C., Clark, R.N., Rockwell, B., Swayze, G.A., King, T., Church, S., Spectral Classification Of Similar Materials Using the Tetracorder Algorithm: the Calcite-Epidote-Chlorite Problem, Proceedings of the Tenth JPL Airborne Earth Science Workshop, Jet Propulsion Laboratory Publication 02-1, pp.93-101.

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

None

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

Spectra have absorptions characteristic of chlorite Because these are intimate mixtures the dark component dominates spectrally. Chlorite spectral features dominate the entire spectra with the presence of calcite indicated only by a slightly deeper 2.3418 micron band relative to the 2.2532 micron band in the calcite rich mixtures.

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 7885 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 7943 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib06a r 24833 g.s.=
LIB_SPECTRA: splib06a r 24892 g.s.=