DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: HS15
MINERAL_TYPE: Inosilicate
MINERAL: Diopside (Pyroxene group)
FORMULA: CaMgSi2O6
FORMULA_HTML: CaMgSi2O6
COLLECTION_LOCALITY: Edwards, NY
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 is not a pure magnesian diopside. An absorption bands at 1.05 indicates the presence of ferrous iron in the crystal structure. A small amount of water in fluid inclusions is indicated by the weak H2O absorptions."
Hunt, G.R., J.W. Salisbury, 1970, Visible and near-infrared spectra of minerals and rocks: I. Silicate minerals. Modern Geology, v. 1, p. 283-300.
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
40 kV - 30 mA, 6.5-9.5 keV
File: diop15.out, -.mdi
References: Borg and Smith (1969); Huebner's reference patterns
Found: Clinopyroxene, trace mica (three basal reflections)
Comment: Superbly crystallized pyroxene. Excellent position and intensity match
with synthetic diopside of composition CaMgSi2O6. The high 2-theta side of the
-221 reflection has a shoulder that is absent in the pattern of the synthetic
material and the pattern calculated by Borg and Smith; however, a similar shoulder
is observed in clinopyroxene HS119.3B and in a pattern of diopside from France.
The pyroxene is diopside and the mica is probably phlogopite.
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem
COMPOSITION_DISCUSSION:
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
av gr sz = 295 µm
Pure sample. Large grains 10% surface coated with 10µm diopside grains. Large diopside grains have 8-10 vol% fluid inclusions, inclined extinction, high relief, biaxial (+), two cleavages at nearly right angles, all consistent with diopside. 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 1429 0.2-3.0µm 200 g.s.= 295 µm
LIB_SPECTRA: splib05a r ____ 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib06a r ____ 1.5-25µm 250 g.s.=