Epidote

Spectrum Details

Modality

FTIR

Category

mineral

Material Type

Sorosilicate

Sample ID

GDS26.a, GDS26.b

Collection Locality

Prince of Wales Island, Alaska

Spectral Purity

1b2b3b4b # Epidote GDS26.a # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2_3_4_ # Epidote GDS26.b # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

Composition / XRD

EPMA # XRF, EPMA, ICP(Trace), WChem COMPOSITION KEYWORD Oxide ASCII Amount Weight Percent, % Oxide html COMPOSITION: SiO2 37.14 wt% SiO2 COMPOSITION: TiO2 0.16 wt% TiO2 COMPOSITION: Al2O3 23.05 wt% Al2O3 COMPOSITION: FeO 14.5 wt% FeO COMPOSITION: MnO 0.18 wt% MnO COMPOSITION: MgO 0.06 wt% MgO COMPOSITION: CaO 22.85 wt% CaO COMPOSITION: Na2O 0.01 wt% Na2O COMPOSITION: K2O 0.02 wt% K2O COMPOSITION: Total 97.97 wt% COMPOSITION: O=Cl,F,S wt% #correction for Cl, F, S COMPOSITION: New Total wt%

Sample Description

Forms series with Clinozoisite. "Results of petrographic examination: Deep green colored epidote crystals 2 cm x 1 cm in size. Looks pure. Microscopic examination indicates pure clean epidote with no alteration." Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263. Sample is in two sieve intervals: (a) 75-200µm and (b) less than 75µm. IMAGE_OF_SAMPLE:

XRD Analysis

Spectrally pure. Epidote plus a large amount of quartz plus a small amount other; M: ~2% magnetite on epidote, ~15% quartz, ~3% plagioclase, no carbonate. (Norma Vergo) "Epidote plus a trace of quartz. No quartz bands are apparent in the spectrum; however, spectral features due to trace of a carbonate were seen and the sample was given acid treatment to remove this contaminant." Salisbury, J. W., Walter, L. W., and Vergo, N., 1987, Mid-Infrared (2.1-25µm) Spectra of Minerals: First Edition, U.S. Geological Survey Open File Report 87-263.

X Units

cm⁻¹

Y Units

Absorbance

Data Points

1,801