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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: Natrolite HS169 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS169

MINERAL_TYPE: Tectosilicate

MINERAL: Natrolite (Zeolite group)

FORMULA: Na2Al2Si3O10*2H20

FORMULA_HTML: Na2Al2Si3O10•2H2O

COLLECTION_LOCALITY: Poonah, India

ORIGINAL_DONOR: Hunt and Salibury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Dimorphous with Tetranantrolite.

"T-22 Natrolite 169B--Poonah, India. Na2Al2Si3O102H2O: The spectral features in this sample are very well resolved and the spectrum displays multiple sharp and weak features, all due to H2O throughout the entire mid- infrared. The main features are at 0.98µ, 1.19µ, 1.46µ, 1.95µ, 2.2µ, and 2.44µ. The differences in these natrolite spectra indicate that the water is less randomly located in the Poonah sample than in the Springfield sample."

Hunt, G.R., J.W. Salisbury, and C.J. Lenhoff, 1973, Visible and near-infrared spectra of minerals and rocks: VI. Additional silicates. Modern Geology, v. 4, p. 85-106.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Pure natrolite. (Norma Vergo)

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

mode:

100 vol% Natrolite
trace Fe-oxide scale

average grain size= 225 µm

Some clear grains 10% vol, the rest are cloudy white. Grains have micron sized fluid or gas inclusions comprising 40 vol% of zeolite grains. Cannot get optic sign. Low relief grains with straight extinction, and sub-rounded habit (not fibrous). These properties are consistent with this sample being natrolite. G. Swayze.

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 3407 0.2-3.0µm 200 g.s.= 225 µm
LIB_SPECTRA: splib05a r 4866 0.2-3.0µm 200 g.s.=


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