Allanite

Spectrum Details

Modality

NIR

Category

mineral

Material Type

Sorosilicate

Sample ID

HS293.1B, HS293.2B, HS293.3B, HS293.4B, HS293.6

Collection Locality

Ontario

Spectral Purity

1b2_3_4_ # HS293.1B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2_3_4_ # HS293.2B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2b3c4_ # HS293.3B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2_3_4_ # HS293.4B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns SPECTRAL_PURITY: 1b2_3_4_ # HS293.6 # 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

"Allanite is an accessory mineral in many granites, granodiorites, monzonites, and syenites, and occurs in large amounts in some limestone skarns and pegmatite's. It is typically a very dark mineral, and this sample is no exception. The high ferric iron and rare earth metal content reduces the reflectivity throughout the visible and very near infrared. The high metal ion content also quenches the hydroxyl bands." Hunt, G.R., J.W. Salisbury, and C.J. Lenhoff, 1973, Visible and near-infrared spectra of minerals and rocks: VI. Additional silicates. Modern Geology, vol. 4, pp 85-106. Grain size fractions are indicated by the extension after the sample number: .1B = IMAGE_OF_SAMPLE:

XRD Analysis

40 kV - 30 mA, 7.0-9.5 keV File: allan293_mdi, *.out; allan2.out, *_mdi (smear mounts on quartz plate) References: JCPDS #25-169 Found: metamict allanite Comment: Few very weak, broad peaks correspond to those of allanite. Small amount of residual allanite; most of the sample has been damaged beyond X-ray diffraction recognition by autoradiation. J.S. Huebner, J. Pickrell, T. Schaefer, written communication 1994

X Units

cm⁻¹

Y Units

Absorbance

Data Points

2,126