Determination of ultra-trace gold in ores by graphite furnace Zeeman atomic absorption spectrometry.

Determination of trace gold in rock samples by a combination of two-stage solvent extraction and graphite furnace atomic absorption spectrometry: The problem of iron interference and its solution.

“…As expected, the sensitivity increased quantitatively by decreasing the volume of MIBK. Interference from foreign elements except iron Shimizu et al (1984) examined the effect of foreign elements on the determination of gold by a combination of GFAAS and one-stage solvent extraction with MIBK. According to their report, the interference from foreign elements except iron is negligible.…”

“…To estimate a reliable mean concentration of gold in rock samples, a combination of solvent extraction with MIBK and graphite furnace atomic absorption spectrometry (GFAAS) is convenient. Although Shimizu et al (1984) reported an excellent deter mination method of gold in ore samples using the combination, the detection limit was 1 ng/g. It is desired to enhance the sensitivity about tenfold in order to determine trace gold in rock samples.…”

“…To eliminate the interference, Shimizu et al (1984) used the back extraction of iron into a diluted acid solution. However, their method was investigated only for the Fe concentration of 0 to 10 mg/10 ml of MIBK.…”