 Johnson Matthey, Hatton Garden, London. |
Resistance Ratio and Purification of Platinum
Platinum Metals Review
Article Synopsis
Accurate correlation between the purity and the properties of platinum is essential both to quantify the properties of the metal with a view to its practical applications and to establish the behaviour of platinum as a representative metal for various physical and chemical measurements. The authors of this paper describe the systematic purification of a platinum bar by vacuum-melting and zonerefining. The final residual resistance ratio obtained was very high. The purity of the platinum, as indicated by optical and mass spectrography, then compared well with the best values previously reported.