A rotating platform, silver-spark technique has been adapted for analysis of rare-earth elements directly, either as solutions or after coprecipitation with a carrier. The platform sample electrode is compared with the rod sample electrode conventionally used, and silver is shown to provide some advantages over copper as an electrode material. Observations are reported on conditions pertaining to the preparation and excitation of samples. Three varied applications of the method are briefly described, and matrix effects are discussed. Platform electrodes are found to be more convenient and adaptable than conventional rods, and the sensitivity of the method is comparable to the copper-spark method for small samples. When larger samples are used, the sensitivity decreases; however, good sensitivity can be obtained by properly selecting conditions or equipment.
Theodore R. Lyon, "Rare-Earth Analysis by a Rotating Platform, Silver-Spark Technique," Appl. Spectrosc. 22, 558-561 (1968)