Ordinary graphite tube can be used to determine various elements, especially those with low atomization temperature. These elements are Cd, Pb, Na, K, Zn and Mg. It is also suitable for low-sensitivity or high-concentration samples. For example, when measuring Al, Fe and Cu, 1 ppb can be measured with a pyrolytic graphite tube and 100 ppb with an ordinary graphite tube. Figure 2 shows the working curve of copper (Cu) measured with a conventional graphite tube and a pyrolytic graphite tube with 20, 40 and 60 ppb for the normal graphite tubes and 2, 4 and 6 for the pyrolytic graphite tubes ppb, shows similar absorption.