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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: Biotite-Chlorite_Mx BR93-36A DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: BR93-36A

MIXTURE_TYPE: Intimate

MIXTURE: Biotite-Chlorite Fe+2 Bearing Rock (Mica and Chlorite groups)

FORMULA: K(Mg,Fe+2)3(Al,Fe+3)Si3O10(OH)2 and (Mg,Fe)3(Si,Al)4O10(OH)2-(Mg,Fe)3(OH)6

FORMULA_HTML: K(Mg,Fe+2)3(Al,Fe+3)Si3O10(OH)2 and (Mg,Fe)3(Si,Al)4O10(OH)2-(Mg,Fe)3(OH)6

COLLECTION_LOCALITY: Rodman Mountains, 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: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

pale green Chlorite rich Biotite Quartz Monzonite rock (fresh surface)

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Minor: Quartz, Albite, Microcline
Trace: Biotite, Pyrite
chlorite obvious in spectrum, probably below detection limit of XRD

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:

Strong iron (Fe+2) absorption features at 0.7 and 1.0, minor OH absorption at 1.4, strong water absorption at 1.9, and strong chlorite features at 2.3 microns, suggest a Mg - rich chlorite with broad Fe+2 absorptions. The 2.3 micron feature is modified by the biotite absorption band.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns