Alunite

Spectrum Details

Modality

FTIR

Category

mineral

Material Type

Sulfate

Sample ID

GDS82

Collection Locality

Sadler, Texas, USA

Spectral Purity

1b2b3c4_ # 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

Low temperature diagenetic variety of alunite. May be from a lake deposit. Composition is 82 mole% Na by atomic absorption: See: Stroffregen, R., and Alpers, C., 1992, Observations on the unit-cell dimensions, H2O contents and del D values of natural and synthetic alunite: American Mineralogist, v.77, p. 1092-1098. IMAGE_OF_SAMPLE:

XRD Analysis

GDS82 Na-(82) alunite 40 kV - 30 mA, 6.5-9.5 keV (n8Oalnt.out) References: JCPDS #41-1467; Huebner's reference patterns Found: alunite, quartz, very very weak reflections at 2.38 and 1.720 A. Comment: the alunite is probably a single phase; its lattice spacing's match those of natroalunite. The alunite has sharp peaks, indicating good crystallinity and compositional homogeneity see: Stroffregen, R., and Alpers, C., 1992, Observations on the unit-cell dimensions, H2O contents and del D values of natural and synthetic alunite: American Mineralogist, v.77, p. 1092-1098.

X Units

cm⁻¹

Y Units

Absorbance

Data Points

1,801