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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: Pyrophyllite SU1421 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: SU1421

MINERAL_TYPE: Phyllosilicate

MINERAL: Pyrophyllite

FORMULA: Al2Si4O10(OH)2

FORMULA_HTML: Al2Si4O10(OH)2

COLLECTION_LOCALITY: unknown

ORIGINAL_DONOR: Ron Lyons, Stanford University

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
File: pyrp1421.mdi (smear on quartz plate)
References: Huebner's reference patterns; PDF #12-203, 16-0344, 12-0203
Sought: Talc, Montmorillonite, Kaolinite, Chlorite, Paragonite, Phlogopite
Found: Pyrophyllite, mica, minor quartz.

Comment: Pattern dominated by very strong basal pyrophyllite peaks having excellent alpha1-alpha2 resolution at high 2 theta resolution. Non-basal pyrophyllite reflections are weak. The pyrophyllite 2M1 (PDF2 #12-0203) is a much better match than triclinic pyrophyllite (25-0022). Unit cell refinement using nine lattice spacing's, using the positions of the quartz peaks as an internal standard, yields a=5.161(4), b=8.934(14), c=18.650(6) angstroms and beta=99.68(5) degrees. Unindexed peaks at 7.63 (moderate), 7.16, 3.80, 3.58, and 3.24 angstroms (all weak) indicate the presence of a fourth phase.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1b2_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 4081 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 5783 0.2-3.0µm 200 g.s.=


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