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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: Hematite WS161 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: WS161

MINERAL_TYPE: Oxide

MINERAL: Hematite (Hematite group)

FORMULA: alpha-Fe2O3

FORMULA_HTML: alpha-Fe2O3

COLLECTION_LOCALITY: Cleator Moor, Cumberland, England

ORIGINAL_DONOR: Ward Science Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Dimorphous with Maghemite.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Comments: Using quartz (100), (101), (112), and (211) reflections as an internal standard for 2 theta, 11 hematite reflections were refined to obtain the cell dimensions a=5.035(1), and b=13.745(4) angstroms. Within the limits of error given above (1 sigma), these dimensions are those of pure Fe2O3 (see PDF2 33-0664).

File: hemat161.mdi, *.out
References: Huebner's reference patterns
Found: Hematite, minor quartz

Comment: Strong, sharp, symmetric hematite reflections indicate excellent crystallinity and suggest compositional heterogeneity. Likewise, the quartz is well crystallized. Hematite peak positions are consistent with Fe2O3 composition.

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE:

None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

mode:
80 vol% hematite
20 vol% quartz

average grain size = 6 µm

Sample is extremely fine grained but contains significant quartz? contamination. G. Swayze.

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 2122 0.2-3.0µm 200 g.s.= 6 µm
LIB_SPECTRA: splib05a r 3284 0.2-3.0µm 200 g.s.=


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