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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: Ferrihydrite GDS75 Syn, F6 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS75 (F6)

MINERAL_TYPE: Oxide

MINERAL: Ferrihydrite (Synthetic)

FORMULA: 5(Fe+3)2O3*9H2O

FORMULA_HTML: 5Fe+32O3•9H2O

COLLECTION_LOCALITY: Synthetic

ORIGINAL_DONOR: Dave Sherman

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

This sample is one of a series of ferrihydrite samples made by Dave Sherman for the following paper:

Sherman, D.M., R.G. Burns, and V.M. Burns, 1982, Spectral characteristics of the iron oxides with application to the Martian bright region mineralogy. Journal of Geophysical Research, v. 87, n. B12, pp. 10169- 10180. (F6 is Dave Sherman's number)

IMAGE_OF_SAMPLE:
Photo of sample

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

the sample is x-ray amorphous - G. Swayze and Ken Esposito.

40 kV - 30mA, 7.3-9.5 kev
File: fehyd75.mdi (smear mount on quartz plate)
References: JCPDS #29-712
Found: Amorphous to CuKalpha X-radiation

Comment: Pattern has a high background but no significant reflections. A weak, very broad maximum is centered around 2.6 Angstroms (Fe-O bond?); an even weaker broad maximum centered about 1.50 Angstroms could be a sample response or an instrumental effect.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: # XRF, EPMA, ICP(Trace), WChem

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

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