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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-Serpentine BR93-22B DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: BR93-22B

MIXTURE_TYPE: Intimate

MIXTURE: Clinochlore (Phyllosilicate - Chlorite group) and Lizardite, Antigorite, and Orthochrysotile (Phyllosilicates - Kaolinite-Serpentine Group)

FORMULA: (Mg,Al,Fe+2)6(Si,Al)4O10(OH)8, Mg3Si2O5(OH)4, (Mg,Fe+2)3Si2O5(OH)4, Mg3Si2O5(OH)4

FORMULA_HTML: (Mg,Al,Fe+2)6(Si,Al)4O10(OH)8, Mg3Si2O5(OH)4, (Mg,Fe+2)3Si2O5(OH)4, Mg3Si2O5(OH)4

COLLECTION_LOCALITY: Bessemer Mine, Iron Ridge, Southeast of Barstow, CA, USA

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

ORIGINAL_DONOR: Eric Livo

CURRENT_SAMPLE_LOCATION: U.S.G.S. Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: U.S.G.S. Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

green chlorite-serpentine bearing skarn rock at contact between dolomite and quartz monzonite intrusive at the Bessemer Mine (iron [magnetite])

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Major: Lizardite
Trace: Chlorite (clinochlore), Antigorite, and Orthochrysotile

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

No additional compositional details available.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

IMAGE_OF_SAMPLE: Not Available

SPECTROSCOPIC_DISCUSSION:

Broad one micron Fe+2 absorption band, with a 1.4 micron chlorite & serpentine feature. The two micron features show a mix of chlorite and serpentine, with a strong 2.32 (OH) feature, a weak 2.25 shoulder (slightly chloritic, mainly serpentine) and a weak 2.38 micron band (lesser serpentine, moderately chloritic)

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: splib05a r 8002 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib06a r 24951 g.s.=