By definition, refractory gold ores contain gold that is resistant to extraction by conventional chemical processing and as a result responds poorly to traditional gold cyanidation techniques such as Carbon-in-Leach (CIL), yielding less than 80% of the contained gold.
Refractory gold consists of extremely fine grained gold particles that are either physically encapsulated within, or chemically bound within, a host mineral. In addition, the host mineral proves impervious to cyanide leaching, which prevents gold extraction.
Refractory gold deposits are metallurgically complex and are therefore often difficult and expensive to develop and operate. Refractory gold ores require either or both physical and chemical pre-treatment, prior to cyanidation.
The proportion of known refractory gold resources relative to overall gold resources, is increasing year on year throughout the world.
The Company is focussed on the utilisation of the Albion Oxidation Process which was developed in Australia and is patented by a subsidiary of global mining group, Glencore PLC.
The Albion Process is an atmospheric leaching process used to oxidise refractory gold sulphide mineral concentrates. Such sulphide minerals are typical of the refractory gold mineralisation found throughout China, the Iberian Peninsula, and various regions in Latin America which are PanTerra Gold’s principal targets.
The Albion Process ensures efficient downstream extraction of contained gold from concentrates by conventional gold processing methods.
The Albion Process treats relatively low value gold froth flotation concentrates in two stages:
Albion Oxidation Reactors
The Albion Process produces a slurry suitable for gold recovery by cyanidation, ultimately producing high value gold doré bars.
Relative to other available refractory gold processing technologies, the Albion Process will be more profitable for:
Importantly, the specific economics for a refractory gold resource are case sensitive, and strongly influenced by the geological, geographical, environmental, and community settings.
The Company has completed the preliminary design and costings for its standard 50,000tpa plant for processing refractory concentrate, which can be up-scaled on a modular basis.
Flowsheet for Albion/CIL Plant