1988 Volume 37 Issue 2 Pages 112-115
This article is a supplemental report for the determination of lead which has not yet be obtained for some of the standard rocks of GSJ in the earlier report.The sample was completely decomposed by gradual heating with HF, HNO3 and HClO4, and evaporated to dryness. In this report, the decomposing conditions for such special rocks as JF-1 and JP-1 were again examined. The decomposed sample was dissolved in 0.5 M HBr, spiked with 212Pb and was passed through a column of Bio Rad AG1-X8 100200 mesh (4 mm i.d.×4cm h). Lead retained on the column was eluted with 6 M HCl after washing the column with 0.5 M HBr. The column yield of the purified lead solution was measured using 212Pb activity and then subjected to the lead concentration measurement by GFAAS. The lead values obtained for JA-2, JA-3, JB-1a, JF-1, JG-1a, JG-2, JG-3, JP-1 of GSJ standard rocks were 19.8, 6.5, 7.5, 33.1, 47.5, 27.6, 33.2, 12.4 and 0.12 ppm, respectively. These values coincided very well with the reported values.
