(For further information on spectroscopy, see:
TITLE: White_Crust LV30 starkeyite DESCRIPT
MIXTURE: Starkeyite + possible other salts
COLLECTION_LOCALITY: Arkansaa river Site 3 km south of Leadville, Colorado, USA
ORIGINAL_DONOR: Gregg Swayze
COLLECTION_LATITUDE: Not Available # degrees and decimal minutes (N or S)
COLLECTION_LONGITUDE: Not Available # degrees and decimal minutes (W or E)
DATUM: Not Available # coordinate datum
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory, Denver, Colorado
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory, Denver, Colorado
White Crust, starkeyite, Arkansas River Site Leadville LV30. This crust formed about saturated fluvial mine tailings rich in pyrite. Apparently water saturated with salts wicked up through permeable fine-grained sand and formed the white salt crust at the surface when the liquid evaporated. It may be possible that the epsomite is mixed with other salts and trace metals may substitute for Mg (e.g. As etc). This type of salt deposit is typical of acid mine drainage and when dissolved by rain or other precipitation causes a quick release of metals into streams.
Starkeyite(Major), Quartz(Major), Albite (trace), Muscovite (trace). Sutley, 2005. The presence of quartz, albite, and muscovite in addition to starkeyite is due to mixing of the white starkeyite coating with underlying fluvial sediments. The spectrum represents the starkeyite only.
COMPOSITIONAL_ANALYSIS_TYPE: NONE # XRF, EM(WDS), ICP(Trace),WChem
The spectral features closely resemble those of epsomite in standard GDS149. The presence of a band at 1.6237 and 2.207 may be diagnostic of starkeyite and perhaps other salts. The XRD analysis includes material from the underlying sediments but the spectrum is of the white crust only.
SPECTRAL_PURITY: 1c2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
|LIB_SPECTRA:||splib05a r 9029||0.2-3.0µm||200||g.s.=|
|LIB_SPECTRA:||splib06a r 26567||g.s.=|