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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Muscovite GDS119 Alamo DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS119

MINERAL_TYPE: Phyllosilicate

MINERAL: Muscovite (Mica group)

FORMULA: KAl2Si3O10(OH)2

FORMULA_HTML: KAl2Si3O10(OH)2

COLLECTION_LOCALITY: Mt. Alamo Mine, Ventura Co. CA

ORIGINAL_DONOR: Jim Post

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

40 kV - 30 mA, 6.5-9.5 keV
References: Bailey (1984, p. 574), Huebner's reference patterns
Found: dioctahedral mica, 2M1 polytype
Sought but not found: quartz, (100) would be distinct if present

Comments: Very similar patterns. Only mica detected. The mica (004) reflection is at 17.6-17.9 degrees 2 theta indicating a large alkali such as potassium (the dioctahedral Na-mica, paragonite, has the (004) reflection at 18.4 degrees). The small sample size required smear mounts, which are responsible for a strong preferred basal orientation in each of the patterns. I'd be surprised if you found any differences in the optical spectra of these eight micas."

J.S. Huebner, J. Pickrell, and J. Randow, 1993, written communication.

END_XRD_ANALYSIS.

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


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 46.28 wt% SiO2
COMPOSITION: TiO2 0.13 wt% TiO2
COMPOSITION: Al2O3 33.34 wt% Al2O3
COMPOSITION: Fe2O3 3.85 wt% Fe2O3
COMPOSITION: MnO 0.04 wt% MnO
COMPOSITION: MgO 0.55 wt% MgO
COMPOSITION: ZnO 0.03 wt% ZnO
COMPOSITION: BaO 0.03 wt% BaO
COMPOSITION: CaO 0.10 wt% CaO
COMPOSITION: Na2O 0.64 wt% Na2O
COMPOSITION: K2O 9.97 wt% K2O
COMPOSITION: H2O+ 4.47 wt% H2O+
COMPOSITION: Total 99.66 wt%
COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S
COMPOSITION: New Total wt%

Jim Post, personal communication, 1991.

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_3_4_ # 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 3342 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 4780 0.2-3.0µm 200 g.s.=


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