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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: Richterite NMNH150800 Amphibole DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: NMNH150800

MINERAL_TYPE: Inosilicate

MINERAL: Richterite (Amphibole group)

FORMULA: Na2Ca(Mg,Fe2+,Mn,Fe3+,Al)5(Si8O22)(OH,F)2

FORMULA_HTML: Na2Ca(Mg,Fe2+,Mn,Fe3+,Al)5(Si8O22)(OH,F)2

COLLECTION_LOCALITY: Wilberforce, Ontario, Canada

ORIGINAL_DONOR: National Museum of Natural History

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

"Results of petrographic examination: Two large (6.49 and 6.45 g) pieces and 2 fragments (4.18 b), black in color. Parts of single crystals. One fragment has large white (calcite) contamination. Crystals also have generally small blotchy inclusions of calcite. Crushed sample treated with HCl. Under the microscope, individual crystals before treatment appear clean and pure except for about 1% calcite 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:

Richterite plus a trace of mica. Infrared spectra do not show a mica hydroxyl band.

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.

Richterite plus a trace of mica (Norma Vergo).

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: EM(WDS) # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 54.87 wt% SiO2
COMPOSITION: TiO2 0.39 wt% TiO2
COMPOSITION: Al2O3 1.97 wt% Al2O3
COMPOSITION: FeO 2.40 wt% FeO
COMPOSITION: MnO 0.20 wt% MnO
COMPOSITION: MgO 22.92 wt% MgO
COMPOSITION: CaO 9.09 wt% CaO
COMPOSITION: Na2O 4.32 wt% Na2O
COMPOSITION: K2O 1.48 wt% K2O
COMPOSITION: Total 97.65 wt%

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

Microprobe analysis by L. Walter shows sample to be homogeneous within and between grains, with a composition typical of richterite. Average of 9 analyses.

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: 1b2_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 4230 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 5952 0.2-3.0µm 200 g.s.=


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