SUN Jun¹, LIU Yun-long², TANG Yong^3*

(1. Department of Resource and Environmental Engineering, Guizhou Institute of Technology, Guiyang 550003, China;
2. School of Management Science, Guizhou University of Finance and Economics, Guiyang 550025, China;
3. Key Laboratory of High-Temperature and High-Pressure Study of the Earth’s Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China)

Abstract: The Shazi deposit, located in Qinglong County of Guizhou Province, is a newly discovered large-scale independent scandium deposit. The iron isotopic compositions of magnetites in fresh basalt, weathered basalt, and mineralized laterite samples have been analyzed. The Fe2O3 contents of fresh basalt and weathered basalt samples vary from 15.41% to 15.51% and from 14.60% to 15.12%, respectively. The δ56Fe values of magnetites of fresh basalt and weathered basalt samples vary from 0.23‰ to 0.29‰ and from 0.02‰ to 0.07‰, respectively. Laterite has the highest Fe2O3 contents ranging from 23.53% to28.95%, but the δ56Fe values, ranging from -0.09‰ to 0.03‰, of magnetites in laterite samples have no big difference to those of magnetites from weathered basalt samples. The change of iron isotopic compositions of magnetites in weathered basalt and laterite samples could be related to the hydrolysis of clinopyroxene. Combined with the existing research results, it is considered that the genesis of scandium mineralization could be related to the deep in-situ hydrolysis and the surficial weathering and leaching of the Emeishan basalt.

Keywords: Qinglong；scandium deposit; iron isotope; Emeishan basalt

ACTA MINERALOGICA SINICA Vol. 40, No.3, 2020, page 323-329