White Crust

Spectrum Details

Modality

NIR

Category

soil

Material Type

Intimate

Sample ID

LV30

Collection Locality

Arkansaa river Site 3 km south of Leadville, Colorado, USA

Spectral Purity

1c2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

Composition / XRD

NONE # XRF, EPMA, ICP(Trace),WChem

Sample Description

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.

XRD Analysis

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.

X Units

cm⁻¹

Y Units

Absorbance

Data Points

2,126