THE CORRECT USE OF PLATINUM IN THE XRF LABORATORY

The use of crucibles and dishes made of platinum and its alloys in the preparation of samples has become an essential feature of XRF analysi s. The broad application of platinum results from its near-perfect oxi dation resistance and its excellent resistance to corrosive attack by metal oxide melts such as XRF fluxing agents. However, a few basic rul es must be adhered to if platinum ware is to give satisfactory service . A number of 'platinum poisons,' which are commonly encountered in sa mples, can cause destruction within a few sample preparation cycles. T hese 'poisons,' the reasons for their corrosive effects and techniques for minimizing or eliminating their influence are outlined. (C) 1997 by John Whey & Sons, Ltd.