PURE GRAPHITE AS A REFERENCE MATERIAL FOR THE DETERMINATION OF TRACE-ELEMENTS - AN INTERLABORATORY COLLABORATIVE STUDY

Seven synthetic graphite powders of different grade of purity were ana lyzed by means of INAA, WDXRF, EDXRF, DC-OES directly and using ICP-MS , ICP-OES, ETAAS and FAAS in combination with various sample preparati on techniques. On the basis of a statistical evaluation of the results obtained, for the trace elements Al, Ca, Cr, Cu, Fe, Mn and Ni, refer ence values were established and, for the elements As, Co, Mg, Mo, Pb, Sb, Si, Sr, Ti, V, Zn and Zr, informative values are given. The analy zed reference materials are commercially available.