Sample Description USGS Spectral Library Version 7

USGS Spectral Library Version 7 Sample Description

Kokaly, R.F., Clark, R.N., Swayze, G.A., Livo, K.E., Hoefen, T.M., Pearson, N.C., Wise, R.A., Benzel, W.M., Lowers, H.A., Driscoll, R.L., and Klein, A.J., 2017, USGS Spectral Library Version 7: U.S. Geological Survey Data Series 1035, 61 p., https://doi.org/10.3133/ds1035
_{For more information on the library, see:
local link
web link}

TITLE: Chlorite-Serpentine BR93-22B DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: BR93-22B

MIXTURE_TYPE: Intimate

MIXTURE: Clinochlore, Lizardite, Antigorite, and Orthochrysotile

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]).
Mixture of Clinochlore (Phyllosilicate-Chlorite group) and Lizardite, Antigorite, and Orthochrysotile (Phyllosilicates-Kaolinite-Serpentine Group).

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

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

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, 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