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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Riebeckite NMHN122689 Amphibole DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: NMHN122689

MINERAL_TYPE: Inosilicate

MINERAL: Riebeckite (Amphibole group)

FORMULA: Na2Fe(+2)3Fe(+3)2Si8O22(OH)2

FORMULA_HTML: Na2Fe3+2Fe2+3Si8O22(OH)2

COLLECTION_LOCALITY: Hurricane Mountain, Conway, New Hampshire

ORIGINAL_DONOR: National Museum of Natural History

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Individual grains of riebeckite appear very pure under the microscope (less than 1% impurities).

Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Pure reibeckite.

Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.

END_XRD_ANALYSIS.

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

COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 50.32 wt% SiO2
COMPOSITION: TiO2 0.53 wt% TiO2
COMPOSITION: Al2O3 0.86 wt% Al2O3
COMPOSITION: FeO 35.27 wt% FeO
COMPOSITION: MnO 1.12 wt% MnO
COMPOSITION: MgO 0.07 wt% MgO
COMPOSITION: CaO 0.08 wt% CaO
COMPOSITION: Na2O 7.95 wt% Na2O
COMPOSITION: K2O 1.41 wt% K2O
COMPOSITION: Total 97.61 wt%

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

Microprobe analysis of hand-picked sample shows it to be homogeneous within and between grains, with typical riebeckite composition. Average of 10 samples.

Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_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: splib04a r 4241 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 5978 0.2-3.0µm 200 g.s.=


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