DOCUMENTATION_FORMAT: MINERAL
SAMPLE_ID: GDS134
MINERAL_TYPE: Hydroxide
MINERAL: Goethite
FORMULA: alpha-FeO(OH)
FORMULA_HTML: alpha-FeO(OH)
COLLECTION_LOCALITY: South Africa
ORIGINAL_DONOR: Dave Sherman
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
SAMPLE_DESCRIPTION:
Sample composed of brown powder.
IMAGE_OF_SAMPLE:
No Image
END_SAMPLE_DESCRIPTION.
XRD_ANALYSIS:
Found: Goethite plus unidentified reflection at 1.484 A Found: a jarosite mineral, subequal quartz, and minor goethite Comment: Goethite intensities match HS-36 and WS-220 (both in this report)
Recent XRD analysis indicates pure goethite. B. Benzel.
END_XRD_ANALYSIS.
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem
COMPOSITION_TRACE: None
COMPOSITION_DISCUSSION:
None.
END_COMPOSITION_DISCUSSION.
MICROSCOPIC_EXAMINATION:
END_MICROSCOPIC_EXAMINATION.
SPECTROSCOPIC_DISCUSSION:
The visible to NIR looks remarkably like that of WS222 -- a pure goethite. There is a slight inflection at 1.42 microns suggesting the the trace presence of an OH-bearing phase.
END_SPECTROSCOPIC_DISCUSSION.
SPECTRAL_PURITY: 1b2b3b4u # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns