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: Erionite+Offretite GDS72 DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: GDS72

MIXTURE_TYPE: Intimate

MIXTURE: Erionite + Offretite (Zeolite group)

FORMULA: (K2Na2Ca,Mg)2[Al4Si14O36]·15H2O + (K2,Ca)5[(Al10Si26)O72]·30H2O

FORMULA_HTML: (K₂Na₂Ca,Mg)₂[Al₄Si₁₄O₃₆]·15H₂O and (K₂,Ca)₅[(Al₁₀Si₂₆)O₇₂·30H₂O

COLLECTION_LOCALITY: Durkee, Oregon

ORIGINAL_DONOR: Unknown

CURRENT_SAMPLE_LOCATION: USGS Spectroscopy sample collection library - Denver, Colorado

ULTIMATE_SAMPLE_LOCATION: USGS Spectroscopy sample collection library - Denver, Colorado

SAMPLE_DESCRIPTION:

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Offretite - major component
Erionite - major component
No other identifiable components

Konnert, Judith and Marta Flohr, 1992, unpublished data, USGS Reston, VA.

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

mode:
95 vol% zeolite
5 vol% contaminant (high birefringence, uniaxial mineral not included in grain size estimate)

avg. grain size = < 5 µm

Elongate prismatic grains (similar to prisms with pyramid terminations) have a very low refractive index. Fine grain size limits other optical determinations, but crystal habit and refractive index are consistent with this sample being a zeolite. G. Swayze.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2b3b4_ # 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 1596	0.2-3.0µm	200	g.s.=
LIB_SPECTRA:	splib05a r 8128	0.2-3.0µm	200	g.s.=
LIB_SPECTRA:	splib06a r 25119			g.s.=
LIB_SPECTRA:	splib06a r 25131			g.s.=