The use of a ge(li-drifted) semiconductor detector and gamma-ray excitation with radioisotopic sources provides an x-ray analytical method that is advantageous for the determination of high-z elements in ores. The 122-kev gamma radiation of co57 was found to be an optimum energy for exciting gold k-radiation. The detection limit for gold was determined to be 30 to 40 ppm using both synthetic standards and analyzed gold ores. With a source strength of 60 mci, a 21-ppm detection limit is obtainable in 3-minute counting times. The sensitivity of the radioisotopic x-ray method for several other high-z elements was also determined. Using co57 for excitation, the detection limits for tungsten, lead, and uranium were 25, 40, and 60 ppm, respectively.