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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: Goethite GDS134 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS134

MINERAL_TYPE: Hydroxide

MINERAL: Goethite

FORMULA: alpha-FeO(OH)

FORMULA_HTML: alpha-FeO(OH)

COLLECTION_LOCALITY: South Africa

ORIGINAL_DONOR: Dave Sherman

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Sample composed of brown powder.

IMAGE_OF_SAMPLE:
No Image

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Found: Goethite plus unidentified reflection at 1.484 A Found: a jarosite mineral, subequal quartz, and minor goethite Comment: Goethite intensities match HS-36 and WS-220 (both in this report)

Recent XRD analysis indicates pure goethite. B. Benzel.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

The visible to NIR looks remarkably like that of WS222 -- a pure goethite. There is a slight inflection at 1.42 microns suggesting the the trace presence of an OH-bearing phase.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2b3b4u # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns