Clark and others 2007 USGS Data Series 231
Spectral Library splib06a Sample Description

(For further information on spectroscopy, see: http://speclab.cr.usgs.gov)

TITLE: Desert_Varnish GDS141 (Entrada) DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: GDS141

MIXTURE_TYPE: Coating # Areal, Intimate, Coating, or Molecular

MIXTURE: Desert_Varnish on Entrada Sandstone

FORMULA: Na4Mn14O27*9H2O + alpha-Fe2O3

FORMULA_HTML: Na₄Mn₁₄O₂₇•9H₂O + alpha -Fe₂O₃

COLLECTION_LOCALITY: Arches National Park, Utah

ORIGINAL_DONOR: Gregg Swayze

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

"Desert varnish invariably consists of birnessite in intimate mixture with hematite and large amounts of clay minerals. The clays are generally of the illite-montmorillonite type with minor kaolinite, but in several samples this concentration ratio is reversed."

Potter, R.M. and G.R. Rossman, 1979, Mineralogy of manganese dendrites and coatings. American Mineralogist, v.64, pp 1219-1226.

This sample is a coating on the Entrada Sandstone.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

END_XRD_ANALYSIS.

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

COMPOSITION_TRACE: None

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 1355	0.2-3.0µm	200	g.s.=
LIB_SPECTRA:	splib05a r 9090	0.2-3.0µm	200	g.s.=
LIB_SPECTRA:	splib06a r 26719			g.s.=