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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: Jarosite GDS99 K 200C Syn DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS99

MINERAL_TYPE: Sulfate

MINERAL: Jarosite (K-jarosite) (Synthetic) (Alunite group)

FORMULA: K(Fe+3)3(SO4)2(OH)6

FORMULA_HTML: KFe+33(SO4)2(OH)6

COLLECTION_LOCALITY: Synthetic

ORIGINAL_DONOR: Roger Stroffregen, SMU

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Sample synthesized at 200C

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

40 kV - 30 mA, 7.3-6.5 keV
Reference: JCPDS #22-827 (jarosite)
Found: Jarosite

Comment: Sharp patterns (GDS99 is exceptional) indicate good crystallinity and compositional homogeneity. All reflections are accounted for by the JCPDS card. However, the samples are not identical. GDS98 has cell hexagonal dimensions a = 7.313(1) and c = 17.060(4) angstroms whereas GDS99 has a = 7.302(1) and c = 17.214(2) angstroms. The difference in c is significant and suggests a composition difference between the two samples. Are there differences in the optical spectra?"

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

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: 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 2425 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 3711 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 3723 1.3-5.3µm 200 g.s.=


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