Globex Mining reports work undertaken for a second client who contracted with Eco Refractory Solutions, Globex’s 75% owned subsidiary which is commercialising a hydrometallurgical process for the recovery of gold from refractory ores. Test work for a first client was able to recover in the range of 95% of the gold from an arsenical refractory gold ore while transforming both the arsenic and sulphides into stable forms suitable for disposal in tailings. The second client has a refractory ore in which the gold is very finely distributed within the crystal lattice of pyrite. Eco’s initial test indicated extraction of 98.1% of the contained gold within a 24 hour period with low cyanide consumption. Two additional follow-up CIL (Carbon in Leach) tests were undertaken to confirm the high extraction rate. The confirmation tests indicated 97.3% and 97.4% gold extraction respectively.
Numerous refractory ore deposits exist which are not being mined due to low gold recoveries using standard recovery methods or environmental problems related in particular to the potential release of arsenic into the environment. Also, a large number of gold mine tailings containing significant unrecovered gold are scattered around the world which may benefit from the use of the method.
The Eco Refractory Solutions hydrometallurgical process is expected to provide numerous benefits. Capital and operating costs are projected to be significantly lower than other methods. The process is in large part a closed system regenerating and recycling the principal reagents. In addition, problems related to the release of arsenic into the environment and acid mine drainage are solved by the transformation of the arsenic and the oxidation of sulphides into environmentally stable forms.
Eco “is extremely pleased that the exclusive hydrometallurgical process is demonstrating the ability to recover more gold than other processes and in an environmentally friendly manner. The process does not require a fine grind, high consumption of cyanide nor expensive infrastructure such as autoclaves, all important advantages over other processes. Eco that with time, [the] technology will become the leading method for recovering gold from refractory ores and tailings.”