{"title":"Germanium-rich nanoparticles in Cu-poor sphalerite: A new mechanism for Ge enrichment","authors":"Guotao Sun, Jia-xi Zhou, Alexandre Cugerone, Mei-fu Zhou, Lingli Zhou","doi":"10.1130/b37014.1","DOIUrl":null,"url":null,"abstract":"Germanium (Ge) is a critical raw material used in high-technology industry (i.e., optical industry) applications, and it is predominantly concentrated in coals and Zn-rich deposits. Previous studies on Zn-rich deposits have documented a correlation between Ge enrichment and the Cu, Ag, and/or Pb-Mn contents in the sphalerite crystal lattice. In this study, we observed Ge-rich nanoparticles hosted in Cu-poor sphalerite from the Banbianjie Zn-Ge deposit (>800 t graded at ∼100 ppm Ge), located in southwest China. Laser-ablation−inductively coupled plasma−mass spectroscopy (LA-ICP-MS) analyses revealed that sphalerite contains very heterogeneous Ge contents (172−1553 ppm). Germanium contents showed positive correlations with Fe, Mn, and Pb contents and negative correlations with Cd contents. Higher Ge contents were detected in the darker zones, whereas the lighter zones showed systematically low Ge contents and were enriched in Cd. Using transmission electron microscopy (TEM), Zn-Ge-Pb-S nanoparticles were identified in the darker zones of sphalerite. These nanoparticles exhibited Ge/Pb ratios (0.48−1.96) very similar to those measured in sphalerite (0.36−2.04), suggesting that Ge could be essentially hosted within the nanoparticles. We propose that the amounts of Zn-Ge-Pb-S nanoparticles are related to a self-organization model induced by rapid crystal growth. This self-organization processes may control the fluctuations of element concentrations in the boundary layer. This study highlights the importance of studying the nanoscale expression of critical elements to understand their incorporation mechanisms into natural materials.","PeriodicalId":55104,"journal":{"name":"Geological Society of America Bulletin","volume":"61 1","pages":""},"PeriodicalIF":3.9000,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geological Society of America Bulletin","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1130/b37014.1","RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Germanium (Ge) is a critical raw material used in high-technology industry (i.e., optical industry) applications, and it is predominantly concentrated in coals and Zn-rich deposits. Previous studies on Zn-rich deposits have documented a correlation between Ge enrichment and the Cu, Ag, and/or Pb-Mn contents in the sphalerite crystal lattice. In this study, we observed Ge-rich nanoparticles hosted in Cu-poor sphalerite from the Banbianjie Zn-Ge deposit (>800 t graded at ∼100 ppm Ge), located in southwest China. Laser-ablation−inductively coupled plasma−mass spectroscopy (LA-ICP-MS) analyses revealed that sphalerite contains very heterogeneous Ge contents (172−1553 ppm). Germanium contents showed positive correlations with Fe, Mn, and Pb contents and negative correlations with Cd contents. Higher Ge contents were detected in the darker zones, whereas the lighter zones showed systematically low Ge contents and were enriched in Cd. Using transmission electron microscopy (TEM), Zn-Ge-Pb-S nanoparticles were identified in the darker zones of sphalerite. These nanoparticles exhibited Ge/Pb ratios (0.48−1.96) very similar to those measured in sphalerite (0.36−2.04), suggesting that Ge could be essentially hosted within the nanoparticles. We propose that the amounts of Zn-Ge-Pb-S nanoparticles are related to a self-organization model induced by rapid crystal growth. This self-organization processes may control the fluctuations of element concentrations in the boundary layer. This study highlights the importance of studying the nanoscale expression of critical elements to understand their incorporation mechanisms into natural materials.
期刊介绍:
The GSA Bulletin is the Society''s premier scholarly journal, published continuously since 1890. Its first editor was William John (WJ) McGee, who was responsible for establishing much of its original style and format. Fully refereed, each bimonthly issue includes 16-20 papers focusing on the most definitive, timely, and classic-style research in all earth-science disciplines. The Bulletin welcomes most contributions that are data-rich, mature studies of broad interest (i.e., of interest to more than one sub-discipline of earth science) and of lasting, archival quality. These include (but are not limited to) studies related to tectonics, structural geology, geochemistry, geophysics, hydrogeology, marine geology, paleoclimatology, planetary geology, quaternary geology/geomorphology, sedimentary geology, stratigraphy, and volcanology. The journal is committed to further developing both the scope of its content and its international profile so that it publishes the most current earth science research that will be of wide interest to geoscientists.