Distribution of critical minerals in the Mount Evelyn Pb–Zn–Ag skarn deposit, Pine Creek Orogen, Northern Territory

Emerging technologies and the increasing adoption of renewable energy have driven an increase in the demand for critical minerals. To match this demand, new sources of critical minerals need to be developed, prompting research into the critical mineral potential of mine waste, historic and existing deposits. This study assesses the distribution of critical minerals in the historic Mount Evelyn Pb–Zn–Ag skarn deposit, located in the Pine Creek Orogen (PCO), Northern Territory, Australia. Primary sulfide mineralisation at the Mount Evelyn deposit comprises sphalerite and galena with lesser arsenopyrite, pyrrhotite, stannite and tetrahedrite. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) spot analyses across the sulfide mineralogy reveal that galena is the preferred host of Se (6.73–703.84 ppm), Te (0.31–31.33 ppm) and Tl (0.42–46.07 ppm); stannite is the preferred host of Ge (12.04–22.85 ppm) and In (138–248 ppm); tetrahedrite is the preferred host of Sb (26.97–33.60 wt%); and arsenopyrite is the preferred host of As (42.51–55.05 wt%), Co (10–1401 ppm) and Ni (5–1996 ppm). SEM-based automated mineralogical mapping (AMICS) was conducted across 12 samples to quantify the sulfide mineralogy. Through the combination of AMICS and LA-ICP-MS data, this study calculates the deportment of critical minerals across the analysed sulfide mineralogy. It is shown that sphalerite is the most important carrier of the critical minerals In, Ga and Ge; galena is the most important carrier of Bi, Tl and Te; tetrahedrite is the most important carrier of Sb; pyrrhotite is the most important carrier of Ni; and arsenopyrite is the most important carrier of As and Co. These findings provide a baseline understanding of the critical mineral distribution in mineralogically similar deposits throughout the PCO and globally. The trace-element composition of the sulfide mineralogy from the Mount Evelyn Pb–Zn–Ag deposit is assessed.Galena is the preferential host of Se, Te and Tl; stannite is the preferential host of Ge and In; tetrahedrite is the preferential host of Sb; and arsenopyrite is the preferential host of As, Co and Ni.When mineral abundance is considered, sphalerite becomes the most important carrier of In, Ga and Ge; galena becomes the most important carrier of Bi; and pyrrhotite becomes the most important carrier of Ni. Galena is the preferential host of Se, Te and Tl; stannite is the preferential host of Ge and In; tetrahedrite is the preferential host of Sb; and arsenopyrite is the preferential host of As, Co and Ni. When mineral abundance is considered, sphalerite becomes the most important carrier of In, Ga and Ge; galena becomes the most important carrier of Bi; and pyrrhotite becomes the most important carrier of Ni.新兴技术与可再生能源的日益普及推动了关键矿产（critical minerals）需求的持续攀升。为匹配这一增长需求，亟需开发新的关键矿产供应来源，这促使学界开展针对矿山废弃物、历史遗留及现有矿床中关键矿产潜力的相关研究。本研究以澳大利亚北领地松克造山带（Pine Creek Orogen, PCO）内的埃文山历史Pb-Zn-Ag矽卡岩矿床为研究对象，评估了其中关键矿产的分布特征。埃文山矿床的原生硫化物矿化以闪锌矿和方铅矿为主，伴生少量毒砂、磁黄铁矿、黝锡矿及黝铜矿。基于激光剥蚀电感耦合等离子体质谱法（Laser Ablation Inductively Coupled Plasma Mass Spectrometry, LA-ICP-MS）的硫化物矿物原位点分析结果显示：方铅矿为硒（Se）、碲（Te）与铊（Tl）的优先赋存载体，其含量范围为6.73~703.84 ppm；黝锡矿为锗（Ge）与铟（In）的优先赋存载体，含量范围分别为12.04~22.85 ppm与138~248 ppm；黝铜矿为锑（Sb）的优先赋存载体，含量范围为26.97~33.60 wt%；毒砂则为砷（As）、钴（Co）与镍（Ni）的优先赋存载体，含量范围分别为42.51~55.05 wt%、10~1401 ppm与5~1996 ppm。研究团队对12件样品开展了基于扫描电镜的自动化矿物学填图（AMICS），以定量表征硫化物矿物的组成特征。结合AMICS与LA-ICP-MS数据，本研究明确了所分析硫化物矿物体系中关键矿产的赋存状态。结果表明：闪锌矿是铟、镓（Ga）与锗的最主要载体；方铅矿是铋（Bi）、铊与碲的最主要载体；黝铜矿是锑的最主要载体；磁黄铁矿是镍的最主要载体；毒砂则是砷与钴的最主要载体。本研究的发现为松克造山带乃至全球范围内矿物学特征相似的矿床中关键矿产分布研究提供了基准参考。