The hydrometallurgy discipline is shifting towards circular processing, resulting in sustainable solutions for managing residual tailings generated during gold processing becoming increasingly important. Gold tailings, typically characterised by fine particle sizes, high silica content, low residual gold concentrations and many other valuable metals, including heavy and critical metals, present both environmental challenges (water, air and soil pollution) and opportunities for valorisation. This review paper examines the reprocessing of fresh and historic tailings, including those dating back to the early 19th century, to recover gold and other valuable metals such as copper, uranium, rare earth elements, and critical metals. Treatment methods including cyanidation, thiosulfate, thiourea, and halide leaching are discussed, with comparisons drawn between their use in value addition to tailings. Some novel methods, such as bioleaching, glycine leaching and deep eutectic solvents, show promising results due to lower operational costs and environmental benefits. Advantages of tailings reprocessing include reduced environmental liabilities as well as potential economic gains, but challenges such as reagent consumption and scalability limit the application. Additionally, this review examines the reuse of barren tailings in road construction, brick manufacturing, and mine backfill. High SiO2 content, fine particle distribution, and low impurity levels (such as arsenic, lead, etc.) enhance their suitability for these applications. Finally, the paper outlines key regulatory frameworks and policy considerations that influence tailings management and reuse, emphasising the need for supportive legislation to encourage sustainable practices. The findings presented in this review are based on a structured and systematic literature review methodology involving comprehensive database searches, rigorous screening, and thematic synthesis. While the literature surveyed extends as far back as 1985, the primary results and data incorporated in this review predominantly originate from studies published in the 2000 s through to 2025 due to the limited information accessible from earlier decades. Overall, reprocessing and repurposing gold tailings align with green mining goals, offering both economic and environmental benefits to the mining sector.
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