Abstract
Porphyry Cu deposits, like Bingham Canyon, offer opportunities for byproduct critical mineral production because of their size and geochemical complexity. Globally, porphyry Cu deposits are the predominant source of byproduct Te, and locally, are important sources of platinum-group metals, Re, Mn, As and Bi. Most current byproduct critical mineral recovery results from opportunities identified when a residue of a refining process is discovered to have anomalous concentrations of a specific element, for example, Te in anode slimes.
This study investigates the deportment of most critical minerals in the Copperton mill among tailings and the Cu and Mo concentrates to identify additional opportunities for recovery. Critical minerals associated with non-sulfide heavy minerals, such as REEs in monazite, W in scheelite, and Zr in zircon, or those commonly found within the lattice of silicate minerals, such as Al, Cs, Ga, Mg, and Rb deport to tailings, but their recovery may prove to be cost prohibitive with current technology. Chalcophile critical minerals show variable deportment among the Cu and Mo concentrates and tailings. Each chalcophile element is undoubtedly hosted by multiple minerals, either as essential elements or in solid solution, which will dictate their deportment and their eventual recovery opportunities downstream of the mill. Characterization of mineral hosts is an ongoing activity. Critical minerals and other commodities associated with pyrite present opportunities for turning current waste streams into value added products to help secure the domestic supply chain if appropriate strategies can be identified.