A rapid, accurate and precise method is presented for rock sample preparation in bulk analysis by LA-ICP-MS. Sample preparation is performed by lithium tetraborate fusion using an apparatus consisting of a 12V (400A) power source coupled with graphite electrodes utilized as crucibles. It allows analyzing few mg of powdered rock and, therefore, it could be useful in the case of low sample availability. An automated analytical protocol that allows determination of 25 elements (Ga, Rb, Sr, Y, Zr, Nb, Ba, rare earth elements, Hf, Ta, Pb, Th, and U) in 24 samples is also presented. Figure of merits related to the complete analytical protocol (sample preparation as fusion beads and LA-ICP-MS analyses) are estimated on five reference materials (USGS BCR2, USGS AGV2, USGS GSP2, CRPG ACE, and USGS RGM1) ranging from basaltic to rhyolitic in composition. The limits of detection range from c.a. 0.1µg·g−1 for Rb to 0.0007µg·g−1 for U. Precision is better than 10% for all elements with concentrations above 2µg·g−1, except for Pb (∼15%). Precision values raise to c.a. 15% for elements in concentration close to the limits of detection. Accuracies are better than 12% for all elements.
Graphite Electrode Lithium Tetraborate Fusion for Trace Element Determination in Bulk Geological Samples by Laser Ablation ICP-MS
PETRELLI, MAURIZIO;PERUGINI, Diego;POLI, Giampiero;PECCERILLO, Angelo
2007
Abstract
A rapid, accurate and precise method is presented for rock sample preparation in bulk analysis by LA-ICP-MS. Sample preparation is performed by lithium tetraborate fusion using an apparatus consisting of a 12V (400A) power source coupled with graphite electrodes utilized as crucibles. It allows analyzing few mg of powdered rock and, therefore, it could be useful in the case of low sample availability. An automated analytical protocol that allows determination of 25 elements (Ga, Rb, Sr, Y, Zr, Nb, Ba, rare earth elements, Hf, Ta, Pb, Th, and U) in 24 samples is also presented. Figure of merits related to the complete analytical protocol (sample preparation as fusion beads and LA-ICP-MS analyses) are estimated on five reference materials (USGS BCR2, USGS AGV2, USGS GSP2, CRPG ACE, and USGS RGM1) ranging from basaltic to rhyolitic in composition. The limits of detection range from c.a. 0.1µg·g−1 for Rb to 0.0007µg·g−1 for U. Precision is better than 10% for all elements with concentrations above 2µg·g−1, except for Pb (∼15%). Precision values raise to c.a. 15% for elements in concentration close to the limits of detection. Accuracies are better than 12% for all elements.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
