A method of ultrasonic leaching has been developed for the destructive analysis of magmatic rock samples1. This method was applied to determine three new elements, Ca, Mg and Al, in magmatic rock samples. The accuracy of the ultrasonic leaching method (CULM) was tested using standard reference materials (SRMs) and the recovery ratio as K1 = CULM/CSRM was defined. Another recovery ratio, K2, was also defined from the results of the conventional dissolution method (CDM), that is K2 = CULM/CCDM. The accuracy and precision of the method are comparable with those of conventional methods. The following recovery ratios were obtained for Ca, Mg and Al, respectively. 96% < K1, Ca < 112% and 95% < K2, Ca < 112%, 93% < K1, Mg < 109% and 94% < K2, Mg < 108% and 91% < K1, Al < 102% and 94% < K2, Al < 107%.

A method of ultrasonic leaching has been developed for the destructive analysis of magmatic rock samples1. This method was applied to determine three new elements, Ca, Mg and Al, in magmatic rock samples. The accuracy of the ultrasonic leaching method (CULM) was tested using standard reference materials (SRMs) and the recovery ratio as K1 = CULM/CSRM was defined. Another recovery ratio, K2, was also defined from the results of the conventional dissolution method (CDM), that is K2 = CULM/CCDM. The accuracy and precision of the method are comparable with those of conventional methods. The following recovery ratios were obtained for Ca, Mg and Al, respectively. 96% < K1, Ca < 112% and 95% < K2, Ca < 112%, 93% < K1, Mg < 109% and 94% < K2, Mg < 108% and 91% < K1, Al < 102% and 94% < K2, Al < 107%.