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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: Pyrolusite HS138 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS138

MINERAL_TYPE: Oxide

MINERAL: Pyrolusite

FORMULA: MnO2

FORMULA_HTML: MnO2

COLLECTION_LOCALITY: Villa Grove, Colorado

ORIGINAL_DONOR: Hunt and Salisbury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Trimorphous with Akhtenskite and Ramsdellite.

The sample measured for the library was HS138.3 which was dry sieved to the grain size interval 74-250µm.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

40 kV - 30 mA, 7.3-9.5 keV
File: mang138.out, -.mdi
References: JCPDS #24-735; Huebner's reference patterns; BUR-4120
Found: Pyrolusite, minor quartz, unidentified weak reflections at 4.2, 2.71, and 2.03 angstroms
Sought but not found: Manganite, ramsdellite, romanechite, ranceite

Comment: Pyrolusite has broad peaks; the relative intensities do not agree with the JCPDS pattern or a pattern of synthetic pyrolusite. The pyrolusite is poorly crystallized. The 4.2 angstroms reflection is in the position of the strongest groutite reflection (110), but the other two unidentified lines are not those of groutite.

J.S.Huebner, J. Pickrell, T. Schaefer, written communication (USGS)

Additional analysis: Pyrolusite (major), quartz (minor), goethite (trace), groutite (?), pyrite (?). Analysis by Steve Sutley

END_XRD_ANALYSIS.

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

COMPOSITION_DISCUSSION:

Originally Hunt and Salisbury thought this sample was Manganite.

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 2895 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r 5705 0.2-3.0µm 200 g.s.=


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