TITLE: Lepidocrosite GDS80 (Sy) DESCRIPT
MINERAL: Lepidocrosite (Synthetic)
COLLECTION_LOCALITY: Synthetic, Dave Sherman
ORIGINAL_DONOR: Dave Sherman
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
Polymorphous with Akaganeite, Feroxyhyte, and Geothite.
"This sample was synthesized by aerial oxidation of a FeCl2 solution at a pH or 6-7. The X ray diffraction pattern of this sample was extremely well-defined, implying a high degree of crystallinity."
The above description may apply to this sample. This sample was one of a series of samples made for the following paper:
Sherman, D.M., R.G. Burns, and V.M. Burns, 1982, Spectral characteristics of the iron oxides with application to the Martian bright region mineralogy. Journal of Geophysical Research, v. 87, n. B12, pp. 10169- 10180.
40 kV - 30 mA, 7.3-9.5 keV
File: lepicr80.out, -.mdi
Reference: JCPDS #8-98, 29-713
Found: lepidocrocite and goethite in subequal proportions
Sought: quartz (see comment)
Comment: Poorly crystallized: weak, broad reflections for both oxides. The goethite (110) and lepidocrocite (120) reflections are in the positions of the quartz (100) and (101) reflections and would prevent X-ray powder detection of a small amount of quartz, if present.
J.S. Huebner, J. Pickrell, T. Schaefer, written communication 1994, Reston, VA.
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem
LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib04a r 2727 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib05a r ____ 0.2-3.0µm 200 g.s.=
LIB_SPECTRA: splib06a r ____ 1.5-25µm 250 g.s.=