(For further information on spectroscopy, see:
http://speclab.cr.usgs.gov)
TITLE: Grossular WS484 Garnet DESCRIPT
DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: WS484
MINERAL_TYPE: Nesosilicate
MINERAL: Grossular (Grossularite, Garnet group)
FORMULA: Ca3Al2(SiO4)3
FORMULA_HTML: Ca3Al2(SiO4)3
COLLECTION_LOCALITY: Asbestos, Quebec
ORIGINAL_DONOR: Wards Natural Science Inc.
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
SAMPLE_DESCRIPTION:
Forms series with Andradite, with Hydrogrossular, with Uvarovite.
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
40 kV - 30 mA, 6.5-9.5 keV
File: gros484.out, *.mdi
References: Borg and Smith (1969), JCPDS #39-368, DHZ, v. 1a(1982), Huebner's
reference patterns
Found: Garnet
Comment: Well crystallized reflections indicate good crystallinity and suggest
chemical homogeneity. The garnet has ao=11.81 Angstroms, consistent with grossular-rich
composition.
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: EM(WDS) # XRF, EM(WDS), ICP(Trace), WChem
COMPOSITION KEYWORD |
Oxide ASCII |
Amount | Weight Percent, % |
Oxide html |
---|---|---|---|---|
COMPOSITION: | SiO2 | 39.710 | wt% | SiO2 |
COMPOSITION: | TiO2 | .253 | wt% | TiO2 |
COMPOSITION: | Al2O3 | 22.580 | wt% | Al2O3 |
COMPOSITION: | Cr2O3 | .006 | wt% | Cr2O3 |
COMPOSITION: | V2O3 | .016 | wt% | V2O3 |
COMPOSITION: | FeO | 1.769 | wt% | FeO |
COMPOSITION: | NiO | .017 | wt% | NiO |
COMPOSITION: | MnO | .690 | wt% | MnO |
COMPOSITION: | MgO | .019 | wt% | MgO |
COMPOSITION: | CaO | 36.170 | wt% | CaO |
COMPOSITION: | Total | 101.230 | wt% | |
COMPOSITION: | O=Cl,F,S | wt% | #correction for Cl, F, S |
COMPOSITION_TRACE: None
COMPOSITION_DISCUSSION:
None.
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
Bimodal grain size distribution:
mode 1: 240 µm @ 75 vol%
mode 2: 15 µm @ 25 vol%
avg. grain size = 210 µm
Trace iron staining. Grains isotropic, with parting, refractive index > glycerin. All consistent with this sample being pure garnet. 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 1868 | 0.2-3.0µm | 200 | g.s.= 210 µm |
LIB_SPECTRA: | splib05a r 2968 | 0.2-3.0µm | 200 | g.s.= |
LIB_SPECTRA: | splib06a r 8685 | g.s.= | ||
LIB_SPECTRA: | splib06a r 8698 | g.s.= |