Analysis of Standard Reference Materials for Zr, Nb, Hf and Ta by ICP‐MS after Lithium Metaborate Fusion and Cupferron Separation*

The concentrations of 27 trace elements in the basalt BIR‐1, as well as in other mafic rock reference materials, have been determined by ICP‐MS, using pure elemental solutions for external calibration and standard additions. Concentrations of rare earth elements in BIR‐1 for the new ICP‐MS data, agree with compiled values, and previous ID‐SSMS results, whereas ICP‐MS data on HFSE's are systematically higher by about 40% to 70% than ID‐SSMS, but are consistent with data generated at other ICP‐MS laboratories.

Section: Resultsmentioning

confidence: 99%

Icp‐ms Analysis of Basalt Bir‐1 for Trace Elements

Xie

Jain

Sun

et al. 1994

“…A 1000 ng/g tungsten solution was analysed to check that no lg6W+ions (m/z=93) were produced under our operating conditions. The possible molecular interferences at m/z=93 of 56Fe37C1 (14) or 29Si1604 ( 6 ) were not observed.…”

Section: Icp Mass Spectrometrymentioning

confidence: 95%

ASSESSMENT OF a SIMPLE METHOD FOR THE DETERMINATION OF NB AND TA AT THE SUB‐μG/G LEVEL IN SILICATE ROCKS BY ICP‐MS

Poitrasson

Télouk³

et al. 1993

We report Nb and Ta data for 15 international silicate rock standards, obtained by inductively coupled plasma‐mass spectrometry (ICP‐MS) measurement following decomposition with HF‐HNOs‐HCI.95 Moand185Re were used as internal standards, and calibration lines were constructed with artificial solutions. Typical relative standard deviations are better than 10% above 0.2 μg/g, and detection limits for Nb and Ta are 40 and 0.8 ng/g, respectively. The results are generally in good agreement with published data. Moreover, this study points out the Nb‐Ta heterogeneity of some standard reference materials on the 100 mg scale.

“…But, using the second method, the 115.6 ± 0.3 µg g -1 value found by the standard additions procedure is also in excellent agreement with spark source mass spectrometry (SSMS) data reported as 116 ± 5 µg g -1 (Jochum et al 1990). Hall and Pelchat (1990), Garbe-Schönberg (1993) and Münker (1998) reported 99 µg g -1 , 116 µg g -1 and 108 µg g -1 Nb respectively, in BE-N by ICP-MS. The reference material BE-N has come to replace BR for which we found 114 µg g -1 and 115 µg g -1 Nb in a previous paper (Etoubleau et al 1985).…”

Section: Comparison With Literature Datamentioning

confidence: 94%

Precise Quantitative Determination of Niobium at Low Level Concentrations in Geological Samples by WD‐XRF

Étoubleau¹,

Cambon²,

Bougault³

et al. 1999

We show in this paper that wavelength dispersive X‐ray fluorescence spectrometry (WD‐XRF) can provide high quality determinations (in terms of accuracy and precision) of Nb in rocks at low level concentrations comparable with data from much more sensitive analytical techniques. Two different sample preparation methods were investigated and combined with a long count time XRF strategy. We first developed a standard additions procedure for rock powders in conjunction with a careful evaluation of the position of analytical lines (peak and background). The precision (2s) varied from within 0.03 μg g−1 to 0.2 μg g−1 in the 0‐5 μg g−1 concentration range, and the detection limit was 0.2 μg g−1. We then separated Nb from the geological matrix using the chemical procedure described by Rehkämper (1994); after separation, Nb was collected on an anion‐exchange membrane which was directly excited by X‐rays. This method yielded a precision (2s) of 0.2 μg g−1 at the μg g−1 level if 100 mg of sample was used, the detection limit being dependent on the mass of sample studied. Detailed descriptions of analytical procedures are given, particularly of innovative aspects of Nb collection on membranes. XRF results obtained by the two sample preparation methods were compared with instrumental neutron activation (INAA) Ta analysis. We found that the ion‐exchange method tended to provide Nb concentrations which were about 10‐15% lower than concentrations found by the standard additions method. We report data for fifteen international reference materials (NIM‐N, AL‐I, AN‐G, BE‐N, MRG‐1, JA‐1, JB‐2, JB‐3, JA‐2, JF‐1, JGB‐1, BIR‐1, DNC‐1, W‐1, W‐2), for which our XRF results are in good agreement with literature data.