art to recover gold 30 it has been found that the light fraction is highly amenable to cyanide treatment and the degree of recovery of gold from the light fraction by dissolution of cyanide in this way is far higher than expected of the order of 97 of the gold present in the light fraction is soluble in cyanide about half of the material leaving the tank 12 is separated into the residual fraction 20 the heavy fraction 18 is sent for further oxidation to the second and remaining tanks in the series train of tanks consequently it is generally possible to reduce the sizes of the second and the remaining tanks by at least a factor of two it is also possible to repeat the light and heavy fraction separation of the material which is produced by the second or any succeeding tank thus making it feasible to reduce yet further the sizes of the remaining tanks in the series train as a variation to the invention all or part of the heavy fraction can be returned as is indicated by means of a dotted line 32 directly to the first tank 12 as opposed to being fed to the second and remaining tanks 14 this reduces the requirement for additional tanks in the first instance if the solution 26 contains base metals such as copper nickel and cobalt then the solution can be treated using any known technique to recover the base metal content 34 another possibility is that.