SAMPLE_ID: HS324.1B, HS324.2B, HS324.3B, HS324.4B
MINERAL: Albite (Plagioclase, Na end member, Feldspar group)
COLLECTION_LOCALITY: South Dakota
ORIGINAL_DONOR: Hunt and Salisbury Collection
CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory
"This is the sodium end member of the albite-anorthite series and is composed of 90 to 100% albite. Its spectrum shows weak features near 0.65 µ (very broad) and near 1.0 µ, suggesting the presence of small amounts of both Fe+3 and Fe+2. The Fe+3 substitutes for aluminum, and the Fe+2 substitutes for the calcium, the latter in whatever anorthite is present. Hydroxyl and water bands are seen near 1.4 and 1.9 µ, and the AlOH bend OH combination feature near 2.2 µ is evident. The strength of this last band suggests incipient alteration of the sample, which is not apparent in hand specimen."
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.
Note: the spectrum of this sample shows a significant 2.2-µm band apparently due to alteration although (see microscopic examination below) it can not be seen by visual examination. Roger N. Clark
Grain size fractions are indicated by the extension after the sample number:
.1B = <5 µm
.2B = <74 µm
.3B = 74-250 µm
.4B = 250-1200 µm
Albite + 3.18(s) anorthite?? (Norma Vergo)
COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem
No compositional analyses available
avg. grain size = 265µm
Pure sample no visible alteration or contamination, clear cleavage bounded crystals. G. Swayze
The spectrum of HS324.1B does not have a 0.62 micron absorption, perhaps because a different portion of the sample was used for grinding to form it.
SPECTRAL_PURITY: 1c2_3_4_ # HS324.1B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2_3_4_ # HS324.2B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2c3b4b # HS324.3B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2_3_4_ # HS324.4B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns