(For further information on spectroscopy, see:
http://speclab.cr.usgs.gov)
TITLE: Augite WS588 Pyroxene DESCRIPT
DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: WS558
MINERAL_TYPE: Inosilicate
MINERAL: Augite (Pyroxene Group, was listed as Diopside)
FORMULA: (Ca,Na)(Mg,Fe,Al,Ti)(Si,Al)2O6
FORMULA_HTML: (Ca,Na)(Mg,Fe,Al,Ti)(Si,Al)2O6
COLLECTION_LOCALITY: Hull, Ontario, Canada
ORIGINAL_DONOR: Wards Mineral Collection
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
SAMPLE_DESCRIPTION:
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
40 kV - 30 mA, 6.7-9.5 keV
File: dipsd588_mdi (smear on qtz plate)
References: Borg and Smith (1969); PDF2 #41-1370, 24-0201; Huebner's reference patterns
and cell refinements, particularly that of diopside from Rotkopschart, Zillertal,
Austria
Found: Clinopyroxene
Comments: Peaks are moderately sharp to sharp but the alpha1-alpha2 components are not
well resolved. The high background is probably due to X-ray fluorescence (suggesting
(Fe and/or Mn are present). All reflections can be indexed as clinopyroxene.
Identification was confirmed with profile-based search-match (ferroan augite,
24-0201). Lattice spacing's are larger than those of WS-592, HS-15, or synthetic
end member diopside, yet smaller than those of hedenbergite HS-10. Conclude
that this material is a clinopyroxene solid solution, not an end member diopside.
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem
COMPOSITION_TRACE: None
COMPOSITION_DISCUSSION:
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
Bimodal grain size distribution:
population 1 grain size = 450 microns at 80 vol%
population 2 grain size = 15 microns at 20 vol%
avg. grain size = 400 microns
Pure sample, inclined extinction, two cleavages at nearly right angles, pale green color, high order colors under cross-polarized light, biaxial (+), weak pleochroism, all consistent with augite. G. Swayze.
END_MICROSCOPIC_EXAMINATION.
SPECTROSCOPIC_DISCUSSION:
END_SPECTROSCOPIC_DISCUSSION.
SPECTRAL_PURITY: 1b2c3b4b # 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 604 | 0.2-3.0µm | 200 | g.s.= 400 µm |
LIB_SPECTRA: | splib05a r 1250 | 0.2-3.0µm | 200 | g.s.= |
LIB_SPECTRA: | splib06a r 3192 | g.s.= | ||
LIB_SPECTRA: | splib06a r 3204 | g.s.= |