TITLE: Erionite+Offretite GDS72 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS72

MINERAL_TYPE: Tectosilicate

MINERAL: Erionite + Offretite (Zeolite group)

FORMULA: (K2,Ca,Na2)2Al4Si14O36*15H20 + (K2,Ca)5Al10Si26O72*30H2O

FORMULA_HTML: (K2,Ca,Na2)2Al4Si14O36•15H20 + (K2,Ca)5Al10Si26O72•30H2O

COLLECTION_LOCALITY: Durkee, Oregon

ORIGINAL_DONOR: Unknown

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

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Konnert, Judith and Marta Flohr, 1992, unpublished data, USGS Reston, VA.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

av gr sz = < 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: 1_2_3_4_

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment

LIB_SPECTRA: splib04a r 1596 0.2-3.0µm 200 g.s.= < 5 µm

LIB_SPECTRA: splib05a r ____ 0.2-3.0µm 200 g.s.=

LIB_SPECTRA: splib06a r ____ 1.5-25µm 250 g.s.=