(For further information on spectroscopy, see:
http://speclab.cr.usgs.gov)
TITLE: Diopside HS317 (Cr) Pyroxene DESCRIPT
DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: HS317
MINERAL_TYPE: Inosilicate
MINERAL: Diopside (Pyroxene group)
FORMULA: CaMgSi2O6
FORMULA_HTML: CaMgSi2O6
COLLECTION_LOCALITY: Finland
ORIGINAL_DONOR: Hunt and Salisbury Collection
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
SAMPLE_DESCRIPTION:
Forms series with Hedenbergite and with Johannsenite.
"This sample contains both ferrous and ferric iron which produce the
absorptions at 0.45, 0.65 and 1.07µm. Ferrous iron substitutes
for Mg in diopside. Cr also substitutes for Mg in this sample."
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:
Primarily pyroxene; best matches are augite and diopside, but this is not definitive. Small amounts of other phases - pectolite, polyhalite, lazulite are possible contributors to residual.
Konnert, Judith and Marta Flohr, 1992, unpublished data, USGS Reston, VA.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
COMPOSITION_DISCUSSION:
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
mode:
94 vol% Diopside
5 vol% Calcite (estimated by fizz in HCl)
1 vol% magnetite (as inclusions in diopside grains)
Very pale green color, some diopside grains white, two cleavages at nearly right angles, inclined extinction, biaxial (+), consistent with diopside. G. Swayze.
END_MICROSCOPIC_EXAMINATION.
SPECTROSCOPIC_DISCUSSION:
END_SPECTROSCOPIC_DISCUSSION.
SPECTRAL_PURITY: 1c2d3b4b # 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 1418 | 0.2-3.0µm | 200 | g.s.= 290 µm |
LIB_SPECTRA: | splib05a r 2415 | 0.2-3.0µm | 200 | g.s.= |
LIB_SPECTRA: | splib06a r 6978 | g.s.= | ||
LIB_SPECTRA: | splib06a r 6990 | g.s.= |