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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+Zeolites HS168 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS168

MINERAL_TYPE: Tectosilicate

MINERAL: Natrolite + Zeolites (Zeolite group)

FORMULA: Na2Al2Si3O10*2H20

FORMULA_HTML: Na2Al2Si3O10•2H2O

COLLECTION_LOCALITY: Springfield, Oregon

ORIGINAL_DONOR: Hunt and Salibury 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.

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: 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 3418 0.2-3.0µm 200 g.s.= 180 µm
LIB_SPECTRA: splib05a r 4889 0.2-3.0µm 200 g.s.=


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