ON THE DETERMINATION OF MINOR ELEMENTS IN SULFIDE MINERALS USING ATOMIC ABSORPTION SPECTROMETRY.

In this paper, some problems that occurred during analyses of minor elements in sulfide minerals employing a Jarrell-Ash AA-1 atomic absorption spectrometer are discussed. The results are summarized as follows: in the presence of 1% Fe, IN-H//2SO//4, 2% pyrrhotite (0. 02g Po/ml), 2% pyrite (0. 02 Py/ml) or other elements, matrix absorption causes significant errors. To correct this interference, a hydrogen lamp is useful; coexisting major elements often have effects on the slope of the working curve of the test element. These errors are corrected by the standard addition method; there is a general trend that matrix absorption varies as time passes after a solution is prepared; and many minor elements such as Co, Ca, Ag, Mg, and others, are co-precipitate with ferric hydroxide. Thus, it is necessary that the precipitates are dissolved with reagents (the filtration method is not suitable).