TITLE: Almandine WS479 Garnet DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: WS479

MINERAL_TYPE: Nesosilicate

MINERAL: Almandine (Garnet group)

FORMULA: (Fe+2)3Al2(SiO4)3

FORMULA_HTML: Fe+23Al2(SiO4)3

COLLECTION_LOCALITY: Ampandrambaika, Malagasy

ORIGINAL_DONOR: Ward Science Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Forms series with Pyrope and with Spessartine.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

None

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: EM # XRF, EM(WDS), ICP(Trace), WChem


COMPOSITION: SiO2 37.34 wt% SiO2
COMPOSITION: TiO2 0.08 wt% TiO2
COMPOSITION: Al2O3 21.93 wt% Al2O3
COMPOSITION: Cr2O3 0.02 wt% Cr2O3
COMPOSITION: V2O3 0.02 wt% V2O3
COMPOSITION: FeO 32.23 wt% FeO
COMPOSITION: NiO 0.01 wt% NiO
COMPOSITION: MnO 1.70 wt% MnO
COMPOSITION: MgO 8.83 wt% MgO
COMPOSITION: CaO 1.62 wt% CaO
COMPOSITION: Total 103.78 wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total 103.78 wt%

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

av gr sz = 125µm Range = 10 - 295µm

Trace of opaques, conchoidal fractured garnet grains, with 15% of garnet grains containing non-isotropic inclusions. 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 193 0.2-3.0µm 200 g.s.= 125 µm

LIB_SPECTRA: splib05a r ____ 0.2-3.0µm 200 g.s.=

LIB_SPECTRA: splib06a r ____ 1.5-25µm 250 g.s.=