Redistribution of germanium during dynamic recrystallization of sphalerite

Abstract

Rare metals are essential to the development of the “green” technologies that are at the core of low-carbon societies. In nature, these metals are frequently present in trace amounts scattered in base metal ore deposits, but the physico-chemical processes that are responsible for their concentration into strategic minerals are still poorly understood. Based on laser-induced breakdown spectroscopy (LIBS), coupled with electron backscattered diffraction (EBSD) analysis, this study shows that plastic deformation and subsequent syntectonic recrystallization of sphalerite (zinc sulfide, ZnS) led to the spatial redistribution of germanium (Ge): from a background level of a few hundreds of parts per million in undeformed primary sphalerite to tens of weight-percent in neocrystallized Ge minerals. During dynamic recrystallization, Ge is likely released from the crystal lattice of parent sphalerite and subsequently concentrated in Ge minerals, leaving behind a Ge-depleted, recrystallized sphalerite matrix. Identifying how rare metals concentrate through deformation and syntectonic recrystallization at the mineral scale is essential to understand the spatial redistribution and localization at the deposit scale. This study highlights the importance of coupling in situ chemical mapping analysis with macro- and microstructural characterization when targeting rare metals in deformed ore.

Short-Pulse Lasers: A Versatile Tool in Creating Novel Nano-/Micro-Structures and Compositional Analysis for Healthcare and Wellbeing Challenges

“…The applications of LIBS-based imaging are extremely varied and cover, for example, the fields of material design [ 212 ], heterogeneous catalysis [ 217 ], paleoclimate [ 210 ], discovery of strategic metals [ 218 , 219 ] and preclinical studies of drugs based on metallic nanoparticles [ 217 , 218 , 219 , 220 ]. We describe here clinical applications of LIBS imaging to illustrate the capabilities of the technique.…”

Behavior of critical metals in metamorphosed Pb-Zn ore deposits: example from the Pyrenean Axial Zone

“…Geological Survey 2019). Chemical extraction from highly concentrated phases (with Ge contents > 1 wt%), previously separated by magnetic or mechanic techniques, could prove to be much more profitable (Cugerone et al 2019).…”

Gallium (Ga), germanium (Ge), thallium (Tl) and cadmium (Cd) resources in China

“…相对于锗在"煤型"含锗矿床中的变化, "铅锌型"含 锗矿床中锗含量稳定. 已有的研究表明, "铅锌型"矿床 中锗的主要赋存矿物为闪锌矿, 极少量以锗的单矿物 形式存在 [35,36] (图2(c), (d)). 在闪锌矿中, 锗主要以四价 形式存在, 其与铜具有较好的相关性, 因此, 锗进入闪 锌矿的机制很可能为3Zn…”

“…(a) Ge-As-Sb oxides from Wulantuga; (b) Ge-Si oxides from Lincang after Ref. [34]; (c) mapping of sphalerites; (d) Cu and Ge contents of sphalerites after Ref [36].…”