Antigorite

Spectrum Details

Modality

FTIR

Category

mineral

Material Type

Phyllosilicate

Sample ID

NMNH96917.a, NMNH96917.b, NMNH96917.c, NMNH96917.d, NMNH96917.e, NMNH96917.f

Collection Locality

Rossa, Antigors Valley, Italy

Spectral Purity

1b2b3b4_ # NMNH96917.a # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2b3b4_ # NMNH96917.b # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2b3b4_ # NMNH96917.c # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2b3b4_ # NMNH96917.d # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2b3b4_ # NMNH96917.e # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2_3_4_ # NMNH96917.f # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

Composition / XRD

XRF # XRF, EPMA, ICP(Trace), WChem

Sample Description

Polymorphous with Clinochrysotile, Lizardite, and Orthochrysotile. The sample was ground in an alumina mortar and pestle and was wet sieved using methanol into 250 µm (a) size fractions. (Letter denotes spectrum designation) The mean grain size of each sieve fraction is: 250 µm.(a) IMAGE_OF_SAMPLE:

XRD Analysis

Analysis by Gene Whitney, USGS Denver, indicate that the sample was representative of its structural class. Analysis by Norma Vergo indicate that the sample contains a medium amount of hornblende and other minerals. Hornblende is estimated to be 6-8 volume percent. Spectrally, the presence of hornblende is not believed to introduce specific absorption features to the antigorite, but may contribute to the general lowering of the reflectance at wavelengths less than 1.5µm. King, T.V.V. and R.N. Clark, 1989, Spectral Characteristics of Chlorites and Mg-Serpentines Using High-Resolution Spectroscopy. J. Geophys. Res., 13,997-14,008. Clark, R.N., T.V.V. King, M. Klejwa, G. Swayze, and N. Vergo, 1990, High spectral resolution reflectance spectroscopy of minerals: J. Geophys Res. 12653-12680.

X Units

cm⁻¹

Y Units

Absorbance

Data Points

1,801