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522669 
Journal Article 
Plesovice zircon - A new natural reference material for U-Pb and Hf isotopic microanalysis 
Slama, J; Kosler, J; Condon, DJ; Crowley, JL; Gerdes, A; Hanchar, JM; Horstwood, MSA; Morris, GA; Nasdala, L; Norberg, N; Schaltegger, U; Schoene, B; Tubrett, MN; Whitehouse, MJ 
2008 
Yes 
Chemical Geology
ISSN: 0009-2541 
249 
1-2 
1-35 
English 
Matrix-matched calibration by natural zircon standards and analysis of natural materials as a reference are the principle methods for achieving accurate results in inicrobeam U-Pb dating and Hf isotopic analysis. We describe a new potential zircon reference material for laser ablation ICP-MS that was extracted from a potassic granulite facies rock collected in the southern part of the Bohemian Massif (Plesovice, Czech Republic). Data from different techniques (ID-TIMS, SIMS and LA ICP-MS) and several laboratories suggest that this zircon has a concordant U-Pb age with a weighted mean Pb-206/U-238 date of 337.13 +/- 0.37 Ma (ID-TIMS, 95% confidence limits, including tracer calibration uncertainty) and U-Pb age homogeneity on the scale used in LA ICP-MS dating. Inhomogeneities in trace element composition due to primary growth zoning prevent its use as a calibration standard for trace element analysis. The content of U varies from 465 ppm in pristine parts of the grains to similar to 3000 ppm in actinide-rich sectors that correspond to pyramidal faces with a high degree of metamictization (present in ca. 30% of the grains). These domains are easily recognized from high intensities on BSE images and should be avoided during the analysis. Hf isotopic composition of the Plesovice zircon (>0.9 wt.% Hf) is homogenous within and between the grains with a mean Hf-176/Hf-177 value of 0.282492 +/- 0.000013 (2SD). The age and Hf isotopic homogeneity of the Plesovice zircon together with its relatively high U and Pb contents make it an ideal calibration and reference material for laser ablation ICP-MS measurements, especially when using low laser energies and/or small diameters of laser beam required for improved spatial resolution. (C) 2007 Elsevier B.V. All rights reserved. 
zircon reference material; laser ablation ICP-MS; Plesovice; U-Pb; dating; Hf isotopes; Bohemian Massif; high-pressure granulites; plasma-mass spectrometry; laser-ablation; icpms; bohemian massif; lu-hf; moldanubian zone; detrital zircons; duluth complex; ion-microprobe; trace-element