Abstract:
The kinetic leaching behaviour of a low-grade surface gold ore and
a high-grade reef ore were evaluated to determine the achievable
gold recovery from these ores and particularly mixtures of these
ores. The reef ore material has a head grade of 13.40 g/t with a
relative standard deviation of 3%, and the unprocessed surface ore
material a head grade of 0.43 g/t with a relative standard deviation
of 15.6%. It is concluded that the kinetic leaching behaviour of
these free milling gold ores during cyanidation, is not influenced by
mixing of reef and surface ore material. No statistically significant
relationship exists between the achievable recovery by direct
cyanidation and the head grade of the material fed. No ideal ratio of
surface ore to reef ore could be established. It is recommended that
these materials should be processed simultaneously to minimize the
costs, security risks, and losses incurred in transportation.
