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.

新兴技术的兴起与可再生能源的日益普及，推动了对关键矿物的需求增长。为满足这一需求，需开发关键矿物的新来源，从而促使研究人员探索矿山废料、历史矿床及现有矿床的关键矿物潜力。本研究评估了历史悠久的伊夫林山铅锌银矽卡岩矿床（Mount Evelyn Pb–Zn–Ag skarn deposit）中关键矿物的分布情况，该矿床位于澳大利亚北领地的松溪造山带（Pine Creek Orogen, PCO）。伊夫林山矿床的原生硫化物矿化主要由闪锌矿和方铅矿组成，伴生少量毒砂、磁黄铁矿、锡石和黝铜矿。通过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）对硫化物矿物进行点分析发现：方铅矿是硒（Se，6.73–703.84 ppm）、碲（Te，0.31–31.33 ppm）和铊（Tl，0.42–46.07 ppm）的优先赋存矿物；锡石是锗（Ge，12.04–22.85 ppm）和铟（In，138–248 ppm）的优先赋存矿物；黝铜矿是锑（Sb，26.97–33.60 wt%）的优先赋存矿物；毒砂是砷（As，42.51–55.05 wt%）、钴（Co，10–1401 ppm）和镍（Ni，5–1996 ppm）的优先赋存矿物。本研究对12个样品进行了基于扫描电镜（Scanning Electron Microscope, SEM）的自动化矿物学mapping（AMICS）分析，以量化硫化物矿物组成。结合AMICS与LA-ICP-MS数据，本研究计算了关键矿物在分析硫化物矿物中的赋存状态。结果表明：闪锌矿是铟、镓和锗的最重要载体；方铅矿是铋、铊和碲的最重要载体；黝铜矿是锑的最重要载体；磁黄铁矿是镍的最重要载体；毒砂是砷和钴的最重要载体。这些发现为松溪造山带（PCO）及全球范围内矿物学特征相似的矿床中关键矿物的分布提供了基准认识。本研究还评估了伊夫林山铅锌银矿床硫化物矿物的微量元素组成：方铅矿是硒、碲和铊的优先赋存矿物；锡石是锗和铟的优先赋存矿物；黝铜矿是锑的优先赋存矿物；毒砂是砷、钴和镍的优先赋存矿物。考虑矿物丰度时，闪锌矿成为铟、镓和锗的最重要载体；方铅矿成为铋的最重要载体；磁黄铁矿成为镍的最重要载体。方铅矿是硒、碲和铊的优先赋存矿物；锡石是锗和铟的优先赋存矿物；黝铜矿是锑的优先赋存矿物；毒砂是砷、钴和镍的优先赋存矿物。考虑矿物丰度时，闪锌矿成为铟、镓和锗的最重要载体；方铅矿成为铋的最重要载体；磁黄铁矿成为镍的最重要载体。