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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: Tremolite NMNH117611 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: NMNH117611

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.

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: EM(WDS) # XRF, EM(WDS), 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_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: 1c2_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 5044 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 6899 0.2-3.0µm 200 g.s.=


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