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: Tremolite NMNH117611 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: NMNH117611.HCl

MINERAL_TYPE: Inosilicate

MINERAL: Tremolite (Amphibole group)

FORMULA: Ca2Mg5Si8O22(OH)2

FORMULA_HTML: Ca₂Mg₅Si₈O₂₂(OH)₂

COLLECTION_LOCALITY: Canada

ORIGINAL_DONOR: Smithsonian Institution

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Forms series with Actinolite and Ferroactinolite.

"Results of petrographic examination: One 21.41g piece, deep brown, and translucent. Part of a single crystal with euhedral faces. Very, very small amount of calcite contamination. Wash with HCl. Under microscope, appears to be virtually all pure, clean tremolite with a very small amount less than 1% of low refractive index impurity. Refractive index indicates very little iron."

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:

Tremolite plus a trace of mica.

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

COMPOSITION
KEYWORD Oxide
ASCII Amount Weight
Percent, % Oxide
html

COMPOSITION: SiO2 54.60 wt% SiO₂

COMPOSITION: TiO2 0.41 wt% TiO₂

COMPOSITION: Al2O3 1.88 wt% Al₂O₃

COMPOSITION: FeO 2.25 wt% FeO

COMPOSITION: MnO 0.19 wt% MnO

COMPOSITION: MgO 23.13 wt% MgO

COMPOSITION: CaO 8.82 wt% CaO

COMPOSITION: Na2O 5.54 wt% Na₂O

COMPOSITION: K2O 1.42 wt% K₂O

COMPOSITION: Total 98.23 wt%

COMPOSITION KEYWORD	Oxide ASCII	Amount	Weight Percent, %	Oxide html
COMPOSITION:	SiO2	54.60	wt%	SiO₂
COMPOSITION:	TiO2	0.41	wt%	TiO₂
COMPOSITION:	Al2O3	1.88	wt%	Al₂O₃
COMPOSITION:	FeO	2.25	wt%	FeO
COMPOSITION:	MnO	0.19	wt%	MnO
COMPOSITION:	MgO	23.13	wt%	MgO
COMPOSITION:	CaO	8.82	wt%	CaO
COMPOSITION:	Na2O	5.54	wt%	Na₂O
COMPOSITION:	K2O	1.42	wt%	K₂O
COMPOSITION:	Total	98.23	wt%

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

"Microprobe analysis shows sample to be homogeneous within and between grains. It has extremely high soda and potash. Thus chemically it is more towards richterite than tremolite. Average of 10 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: 1b2b3b4_ # NMNH117611.HCl # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns