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Clark and others 2007 USGS Data Series 231
Spectral Library splib06a Sample Description

(For further information on spectroscopy, see: http://speclab.cr.usgs.gov)

TITLE: Natrolite+Zeolites HS168 DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: HS168

MIXTURE_TYPE: Intimate

MIXTURE: Natrolite + Zeolites (Zeolite group)

FORMULA: Na2Al2Si3O10*2H20

FORMULA_HTML: Na2Al2Si3O10•2H2O

COLLECTION_LOCALITY: Springfield, Oregon

ORIGINAL_DONOR: Hunt and Salisbury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Dimorphous with Tetranatrolite.

"T-21 Natrolite 168B--Springfield, Ore. Na2Al2- Si3O10.2H2O: This Zeolite occurs in cavities in basalt's and related rocks and also as an alteration product of nepheline, sodalite or plagioclase. Its major features occur at 0.85µ, 1.165µ, 1.44µ, and 1.95µ. These bands are considerably sharper than in the stilbite."

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.

IMAGE_OF_SAMPLE:
Photo of sample

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Natrolite + large amount of analcime + small amount of clinoptilolite + large amount other. (Norma Vergo)

Spectrally contaminated by other zeolites. (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:

40 vol% Natrolite
30 vol% Analcime (isotropic, low relief, conchoidal fracture)
20 vol% Clinoptilolite
10 vol% Calcite
trace Fe-oxide scale

Not many gas or fluid inclusions in natrolite. Straight extinction, prismatic habit, length slow, all properties consistent with natrolite. Clear conchoidally fractured grains have low relief, 1st order gray (nearly isotropic), undulose extinction, and rutile inclusions, and are probably analcime grains. Flat blades with length slow character are probably Clinoptilolite. Calcite fizzes in HCl. This sample is very contaminated in a modal sense. G. Swayze.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2b3b4b # 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 3418 0.2-3.0µm 200 g.s.= 180 µm
LIB_SPECTRA: splib05a r 4889 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib06a r 26211 g.s.=
LIB_SPECTRA: splib06a r 26223 g.s.=