Sample Description USGS Spectral Library Version 7

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
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TITLE: Richterite NMNH150800 HCl 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.

IMAGE_OF_SAMPLE:

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: EPMA # XRF, EPMA, 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 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:

Infrared spectra do not show a mica hydroxyl band.

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2b3b4_ # NMNH150800 # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns