DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: GDS111
MINERAL_TYPE: Phyllosilicate
MINERAL: Muscovite (Fe-rich, Mica group)
FORMULA: KAl2Si3O10(OH)2
FORMULA_HTML: KAl2Si3O10(OH)2
COLLECTION_LOCALITY: Guatemala
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, 7.2-9.5 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."
J.S. Huebner, J. Pickrell, and J. Randow, 1993, written communication.
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: XRF # XRF, EPMA, ICP(Trace), WChem
COMPOSITION KEYWORD |
Oxide ASCII |
Amount | Weight Percent, % |
Oxide html |
---|---|---|---|---|
COMPOSITION: | SiO2 | 47.87 | wt% | SiO2 |
COMPOSITION: | TiO2 | 0.69 | wt% | TiO2 |
COMPOSITION: | Al2O3 | 28.03 | wt% | Al2O3 |
COMPOSITION: | Fe2O3 | 7.20 | wt% | Fe2O3 |
COMPOSITION: | NiO | 0.01 | wt% | NiO |
COMPOSITION: | MnO | 0.07 | wt% | MnO |
COMPOSITION: | MgO | 0.94 | wt% | MgO |
COMPOSITION: | ZnO | 0.06 | wt% | ZnO |
COMPOSITION: | BaO | 0.28 | wt% | BaO |
COMPOSITION: | CaO | 0.24 | wt% | CaO |
COMPOSITION: | K2O | 10.16 | wt% | K2O |
COMPOSITION: | H2O+ | 4.44 | wt% | H2O+ |
COMPOSITION: | Total | 99.99 | 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: 1a2a3a4a # GDS111 # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns