DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: HS111.1B, HS111.2B, HS111.3B, HS111.4B, HS111.6
MINERAL_TYPE: Nesosilicate
MINERAL: Andradite (Garnet group)
FORMULA: Ca3(Fe+3)2(SiO4)3
FORMULA_HTML: Ca3Fe+32(SiO4)3
COLLECTION_LOCALITY: Graham County, Arizona
ORIGINAL_DONOR: Wards Scientific
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
SAMPLE_DESCRIPTION:
Forms series with Grossular and with Schorlomite.
Under a hand lens the sample appears brown. Individual grains have varying shades of brown with an overall "salt and pepper" effect. The visible and near-IR spectrum shows spectrally pure andradite.
Grain size fractions are indicated by the extension after the sample number:
.1B = <5 µm
.2B = <74 µm
.3B = 74-250 µm
.4B = 250-1200 µm
.6 = cut slab
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
Andradite + Quartz - by Norma Vergo
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem
COMPOSITION_TRACE: None
COMPOSITION_DISCUSSION:
None
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
Optical examination gives the following mineral mode:
85 vol% andradite
15 vol% Fe-stained mineral or andradite
avg. grain size = 270µm
Conchoidally fractured andradite grains some of which are partially Fe-stain coated. Entire grains Fe-stained may be different phase or andradite. G. Swayze
END_MICROSCOPIC_EXAMINATION.
SPECTROSCOPIC_DISCUSSION:
END_SPECTROSCOPIC_DISCUSSION.
SPECTRAL_PURITY: 1b2_3_4_ # HS111.1B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1b2_3_4_ # HS111.2B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1b2b3b4b # HS111.3B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1b2_3_4_ # HS111.4B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1b2_3_4_ # HS111.6 # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns