Recently, I used Cameca 1280HR to measure trace elements in basaltic glasses. The accuracy of most elements were +/-1-30%. However, Lu, Hf, Ta and Th (the contents of these elements are about 0.5-5 ppm) had poor accuracy (about 50% or even worse). The peaks of 180Hf and 181Ta were not good and it seemed there were some interferences (maybe 164Dy16O and 165Ho16O). But I don't know how to correct these interferences. The peaks of 175Lu and 232Th were normal. The interferences may be exactly overlaping Lu and 232Th. Could someone give me some advice to improve the accuracy? Thank you very much.