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USGS Spectral Library Version 7 Sample Description

Kokaly, R.F., Clark, R.N., Swayze, G.A., Livo, K.E., Hoefen, T.M., Pearson, N.C., Wise, R.A., Benzel, W.M., Lowers, H.A., Driscoll, R.L., and Klein, A.J., 2017, USGS Spectral Library Version 7: U.S. Geological Survey Data Series 1035, 61 p., https://doi.org/10.3133/ds1035
For more information on the library, see: local link web link

TITLE: Bastnaesite_REE WS320 crystl DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: WS320

MINERAL_TYPE: Carbonate-Fluoride

MINERAL: Bastnaesite

FORMULA: (Ce,La,Y)(CO3)F

FORMULA_HTML: (Ce,La,Y)(CO3)F

COLLECTION_LOCALITY: Nipton, California, USA

ORIGINAL_DONOR: Wards Scientific

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION: Brown to pink veins in a highly fractured white matrix (barite).

IMAGE_OF_SAMPLE:

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

X-ray diffraction analysis found quartz, barite and minor bastnesite (R. Driscoll).

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION: The spectrum of this sample was measured on a brown and pink vein of bastnaesite. Bastnaesite Ward Sample WS320 XRD results show that the sample is contaminated with quartz and barite but both minerals do not have VNIR-SWIR absorption features and donít contribute to the REE absorptions between 0.35 and 2.1 microns. It should be representative of relatively pure bastnaesite. There are numerous intense sharp absorptions (f-f orbital electronic transitions) throughout the 0.35 to 2.5 micron region presumably due to variable proportions of lanthanide series rare earth elements (i.e., Nd, Sm, and others). Absorptions in the SWIR exhibit overlapping absorptions, broader bands and vibrational absorptions due to potential CO3 combination and overtone bands. This makes band assignment more difficult and multiple REEs could be present in a given wavelength region. (T. Hoefen and G. Swayze)

END_SPECTROSCOPIC_DISCUSSION.

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