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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: Phlogopite HS23 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS23

MINERAL_TYPE: Phyllosilicate

MINERAL: Phlogopite (Mica group)

FORMULA: KMg3Si3AlO10(F,OH)2

FORMULA_HTML: KMg3Si3AlO10(F,OH)2

COLLECTION_LOCALITY: Ontario

ORIGINAL_DONOR: Hunt and Salibury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Forms series with Biotite.

"P-15 Phlogopite 23B--Ontario. K2(Mg, Fe2+)6- (Si6Al2P20)(OH, F)4. Phlogopite occurs most commonly in metamorphosed limestone's and in ultrabasic rocks. It is difficult to obtain a reliable spectrum from this sample because of interference bands. The spectrum falls off quite steadily from 2.0µ into the blue of the visible, although no electronic features are well resolved. The absorption is, however, due to generalized absorption by both Fe2+ and Fe3+, the latter substituting for Al. The important features in the spectrum are the OH vibrational features at 1.38µ, 2.325µ, and 2.385µ. The latter two features are displaced from the location of the most intense bands in the other micas, as a result of the trioctahedral structure which provides for the domination of the MgOH bending modes combinations rather than the AlOH bending modes in the dioctahedral micas. However, there is still evidence for the possibility of some AlOH bending mode combination displayed by the weak features near 2.2µ, being present although these features could be due to the more common OH-lattice combinations."

Hunt, G.R., J.W. Salisbury, and C.J. Lenhoff, 1973, Visible and near-infrared spectra of minerals and rocks: VI. Additional silicates. Modern Geology, v. 4, p. 85-106.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Phlogopite - pure. Spectrally pure. (Norma Vergo)

END_XRD_ANALYSIS.

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


COMPOSITION
KEYWORD
Oxide
ASCII
Amount Weight
Percent, %
Oxide
html
COMPOSITION: SiO2 39.690 wt% SiO2
COMPOSITION: TiO2 1.233 wt% TiO2
COMPOSITION: Al2O3 14.350 wt% Al2O3
COMPOSITION: FeO 1.799 wt% FeO
COMPOSITION: MnO .0285 wt% MnO
COMPOSITION: MgO 25.540 wt% MgO
COMPOSITION: CaO 0.015 wt% CaO
COMPOSITION: Na2O 0.262 wt% Na2O
COMPOSITION: K2O 10.020 wt% K2O
COMPOSITION: Cl 0.072 wt% Cl
COMPOSITION: F 3.864 wt% F
COMPOSITION: Total 96.874 wt%
COMPOSITION: O=Cl,F,S 1.643 wt% #correction for Cl, F, S
COMPOSITION: New Total 95.231 wt%

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

average of 6 spot analyses

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 3874 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 5401 0.2-3.0µm 200 g.s.=


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