A conventional high-performance liquid chromatograph (HPLC) has been evaluated for the rapid isolation of pure fractions of Nd, Sr, Sm and Rb from dissolved-rock solutions. Fractions of Rb, Sr and Nd + Sm were separated in 10 min. from a rock solution, and the Nd and Sm were separated from one another with a second 10-min. separation. Fractions of Nd and Sr were cleaner than those obtained by classical ion-exchange procedures, and stable-ion signals were obtained for Nd fractions containing ⩾ 30 ng Nd. Conventional laboratory facilities were used for all HPLC procedures except filament loading, and total sample blanks were 80 pg for Nd and 250 pg for Sr. No significant mass interferences were observed for Sr or Nd fractions. The agreement observed between HPLC and conventional results for and isotopic ratios was within ±0.003% (1σ) for BCR-1 standard and a number of basalts and phonolites.