Impact of Pyrite Textures Prevalence on Flotation Performance in Mount Isa Copper Orebodies

Abstract

ABSTRACT Pyrite, the most abundant sulfide mineral in base-metal deposits, presents significant challenges in mineral processing due to its deleterious effects when not properly managed. Its undesirable association with valuable minerals leads to low-quality concentrates, hindering smelting processes. Pyrite’s distinct textures and variable elemental compositions affect its floatability, with complex textures challenging to depress. Moreover, since multiple textures can be present within an orebody, their relative proportion in the ore could affect the overall flotation performance. Therefore, understanding the types of pyrite present, their abundance, and how they affect the flotation behavior of the ore is critical for an efficient depression and possible reclamation of pyrite. At the Mount Isa copper deposit, framboidal or ‘carbonaceous’ pyrite has been an ongoing challenge to the copper concentration operation, reducing the flotation circuit’s efficiency. Previous work by Yenial-Arslan et al. showed that high pyrite recoveries could be strongly linked to the prevalence of fine-grained pyrite. However, samples belonging to the coarse pyrite domain exhibited low natural floatability. This study further investigates the effect of the prevalence of pyrite textures on the flotation performance of copper orebodies at the Mount Isa deposit. The prevalence of pyrite textures was quantified and statistically linked to the natural floatability of pyrite, proving that fine-grained and framboidal pyrite greatly influence pyrite’s overall recovery. Furthermore, various mineral characterization techniques, such as synchrotron X-ray fluorescence microscopy (XFM) analysis, were used to explore how the natural floatability of pyrite was affected.