A relationship is predicted between oxidic nickel in slag, oxygen in matte and Ni/Fe ratio in matte after the examination of thirty sets of contiguous matte and slag samples taken from industrial nickel smelters._x000D_
Oxidic nickel in slag is found to increase with increase in oxygen content of matte of constant Ni/Fe ratio, and it is proposed that the relationship may be used to predict nickel solubility in slag from a knowledge of matte composition alone.