This section assesses Australia's resource potential for selected critical commodities. In Table 1.5.1 the key results of this review are summarized in two groups of commodities: those with category one resource potential and those with category two resource potential. These are extracted from Table 1.5.2 which presents a more comprehensive assessment, including those rated with category three resource potential (see below). These tables are the result of a synthesis and analysis of Parts 1 and 2 of this report.
Within each of the category one and category two resource potential categories the commodities are listed in order of criticality.
The assessments of resource potential in Table 1.5.1 are subjective judgements based on:
It is notable that most of the commodities that have a category-one resource potential are also regarded as critical by some countries that have undertaken studies of material criticality. There are several commodities that Australia has category one potential for resources, however they are considered to have category three criticality. One example of such commodities is copper, which has category one resource potential despite its category three criticality score as: (a) the growth outlook for copper is strong; (b) Australia's geology and resource potential are considered very favorable for discoveries of new copper resources; (c) and the market size is very large.
Seven of the commodities rated as having category two resource potential also are considered critical by the world's major economies (antimony, indium, lithium, molybdenum, niobium, tantalum, tungsten). Also in the category two group are six other commodities with a category two criticality ranking (beryllium, bismuth, graphite, manganese, tin, titanium). Only one other commodity, thorium, was assigned category two potential despite its category three criticality rating. This assessment reflects the possible growth in markets if emerging and new technologies using thorium (nuclear power generation) have greater rather than lesser uptakes in the medium to long term. The assessment also takes into account Australia's considerable resources of thorium. Helium was also assigned category two resource potential although it was not considered in criticality rankings.
Among the 12 commodities rated as having category three resource potential (Table 1.5.2), two are considered to be of category one criticality by countries (gallium and vanadium) and three of medium criticality (germanium, selenium and strontium). Many of these commodities are of small market size and/or have limited growth outlooks, and/or have low known and potential endowment in Australia. These judgements are a snapshot of the present situation which will change over time. For example, Olympic Dam is a multi-mineral ore body that is mined for uranium, copper, gold and silver, but also contains significant amounts of rare-earth elements and other critical commodities.
1.5.2 A mineral systems perspective on Australia's resource potential
An important conclusion of this report is that most of the commodities assessed as having category one and category two resource potential are geologically associated with three mineral system groups. In addition, a fourth opportunity exists for critical commodities that can be produced as by-products from existing operations.
Mafic-ultramafic igneous-related mineral systems (Ni, PGE, Cr, Cu, Co, Ti)
The nickel and platinum-group element industries globally are very large yet known resources and production are concentrated in relatively few countries, for example platinum-group element industries in South Africa and Russia. Economic platinum-group element deposits are extremely rare and highly valuable. Australia's resource potential is high for discovery of major mafic-ultramafic intrusion-hosted nickel, platinum-group element and chromium deposits. Areas of known and inferred resource potential for these commodities are shown in Figure 1.5.1. A key issue is that many of the prospective terranes for sulfide nickel and platinum-group element deposits are concealed by layers of cover rocks that may be metres to hundreds of metres thick.
Australia also has major known resources of lateritic nickel, some of which are currently being exploited. There are potential opportunities to develop technologies for more efficient extraction of nickel and other associated elements such as scandium from these lateritic deposits.
Intermediate to felsic igneous-related mineral systems (Cu, REE, Be, Li, Mo, Nb, Ta, Sn, W, Bi, Sb)
Commodities associated with intermediate to felsic igneous-related mineral systems are varied. In detail the composition of magmas with which these systems are associated are also varied and include intermediate, evolved felsic and alkaline magmas. Unlike the mafic-ultramafic igneous-related systems, resources and production of commodities associated with intermediate to felsic magmatism are much more widespread, with Australia possessing significant resources of many of the associated critical commodities. At present, Australia is a major producer of copper and lithium, and in the past it has been a major producer of antimony, tantalum, tin and tungsten. Regions of current and historic production (some of which have significant identified resources) must be considered regions with significant potential for additional discovery (Figure 1.5.2).
In addition to commodities with historic or current production, Australia is emerging as a potential producer for commodities such as rare-earth elements and molybdenum.
Surface-related mineral systems, particularly heavy mineral sand deposits (Zr, Ti, REE, Th)
Use of critical commodities:
(a) Magnets in wind generators. (b) Photovoltaics.
The third mineral system offering category one resource potential for Australia is heavy mineral sands. Government supported work in South Australia was crucial in the identification and discovery of a major new mineral sands province, resulting in several currently operating mines. These mineral systems not only host major industrial commodities such as titanium and zirconium but also contain significant resources of rare-earth elements and thorium. Figure 1.5.3 shows the distribution of major historic and existing mineral sand operations in Australia.
Light rare-earth elements in mineral sand deposits represent very large resources that may be exploited in the future. The rare-earth elements and thorium in these deposits are mainly locked up in monazite and are not currently extracted. Monazite is returned to the pit in a dispersed form, as required by mining regulations. Extraction of rare-earth elements may be more viable where low-thorium monazite is present in mineral sand deposits.
Recovery of by-products from existing ores and concentrates
Several commodities are produced as co-products or by-products of major metal mining; platinum-group element recovery from some nickel ores is an example of co-production. Among those commodities assessed as having medium resource potential, antimony, bismuth and indium are by-products of base metal and/or gold mining, and lower resource potential by-products include cadmium, gallium, germanium, mercury, rhenium, selenium, tellurium and vanadium. The Olympic Dam deposit is one of the largest rare-earth element resources in the world, but at present rare-earth elements are not recovered. Where recovery is currently uneconomic, there may be improvements in mineral processing for ores containing significant concentrations of co-product and by-product elements.
For many Australian mines the minor-element compositions of ores and concentrates are not well known or not published. However, preliminary calculations in this study for several of Australia's base and precious metal ore bodies indicate the potential for substantial resources of elements such as antimony, indium cadmium, gallium, germanium, mercury, rhenium, selenium, and tellurium (see Part 2). In addition, it is known that gallium, germanium and rare-earth elements are enriched in some coal deposits (Dai et al., 2006; Qi et al., 2007; Seredin, 2005). Finally, phosphate deposits are a potentially important source of rare-earth elements as well as other metals such as uranium; Australia is relatively well endowed with phosphate deposits such as those in the Georgina Basin (Northern Territory and Queensland), but the minor-metal compositions of these deposits are not well understood.