| Abstract: | Many advanced energy and environmentally relevant technologies rely on metals that have been identified as critical, or whose availability may be limited. Several of these elements are produced mostly as by‐products of mining other base metals (carriers). This by‐product dependence has been proposed as a significant supply‐risk indicator by the materials criticality community. This article provides new quantitative evidence that, in several cases, by‐product metals’ availability may not be directly limited by carrier supply. We perform an assessment based on characteristics essential to by‐product metals, including physical concentration, market value of metals, and extraction technology efficiency. We analyze 40 carrier/by‐product pairs and identify five ‘high‐by‐product’ pairs. We assess the supply responsiveness of these metals. Our analysis suggests that rather than limited primary production of carrier, lack of incentive for improving recovery efficiency may limit availability of the by‐product. This behavior is found in the zinc‐indium and copper‐selenium systems. For germanium, on the other hand, we instead propose influence from the by‐product market itself leading to price inelasticity of supply. As a complement to other quantitative methods developed for material systems, such as material flow analysis, we provide an essential technoeconomic analysis of the by‐product metals problem by employing cluster analysis and econometric modeling. This approach provides insight into supply‐risk mitigation strategies related to extraction efficiency and supply‐chain structure. |
