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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Neodymium_Oxide GDS34 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS34

MINERAL_TYPE: Oxide

MINERAL: Neodymium_Oxide

FORMULA: Nd2O3

FORMULA_HTML: Nd2O3

COLLECTION_LOCALITY: REE Standard Reagent

ORIGINAL_DONOR: None

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Spex Standard 84.3% Nd Lot No. 02831R

Reflectance spectra for reagent-grade Eu2O3, Nd2O3, Sm2O3, and Pr2O3 (Fig. 2) show the intense, narrow absorption bands caused by electronic transitions in trivalent rare earth elements (White, 1967; Dieke and Crosswhite, 1963). The absorption patterns produced by each of these oxides is distinctive for the particular rare earth element involved. The positions of the major bands for Nd2O3 and Sm2O3 are indicated in Table 2. Absorption features that occur near 1.4 and 1.9 µ cannot be unambiguously assigned to water or hydroxyl since some rare earth element oxides, notably Sm2O3 and Pr2O3, have electronic bands in these wavelength regions (Fig. 2). The cause of the 2.35µ bands in two of the rare earth element oxide samples (Fig. 2) also has not been determined. Although White (1967) tentatively attributed similar features to water, the bands could be produced by minor amounts of CO3 or possibly by an undocumented REE-OH vibrational overtone. No carbonate or hydroxyl-bearing phases were detected by X-ray diffraction analysis of the rare earth element oxide samples."

Rowan, Lawrence C., Kingston, Marguerite J., Crowley, James K., Spectral Reflectance of Carbonatites and Related Alkalic Igneous Rocks: Selected Samples from Four North American Localities, Economic Geology, Vol 81, 1986, pp. 857-871.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

40 kV - 30 mA, 6.5-9.5 keV
File: ndoxid34.mdi, *.out (smear mount on quartz plate)
References: JCPDS #21-579, 43-1023, 6-601, 13-85; Huebner's reference patterns.
Found: Neodymium Hydroxide, Nd(OH)3

Comment: The hydroxide reflections are sharp at 2 theta < 35 degrees, broad at 2 theta = 35-70 degrees. The alpha1-alpha2 reflections are not resolved. A weak, broad, unindexed reflection at 1.77 angstroms corresponds to a weak reflection of high-pressure Nd2O3, but since this reflection is also present in Huebner's reference pattern of reagent-grade Nd2O3, it may be a Nd-hydroxide peak that was omitted by JCPDS.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

No visible impurities. G. Swayze.

average grain size= 4 µm

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib04a r 3439 0.2-3.0µm 200 g.s.= 4 µm
LIB_SPECTRA: splib05a r 4902 0.2-3.0µm 200 g.s.=


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