Analysis of mineralogical characteristics of imported iron ore from different countries: Constraints from maceral compositions and elemental analysis

Abstract

China is the largest importer of iron ore resources. Analyzing the mineralogical characteristics of imported iron ore samples imported from different countries can provide a reference for identifying the source of iron ore and solid waste attributes. In this paper, iron ore samples imported from 11 countries were used to determine their elemental compositions and mineral assemblages by polarized light microscopy investigation, X-ray fluorescence spectroscopy (XRF) and pyrite/magnetite LA-ICP-MS element analysis. These results are applied to explore the formation environment of iron minerals. XRF analysis results show that the main elements of iron ore samples are Fe and O, followed by Si, Ca, Al, Mn, Tb, Ti, Mg, P, and S. These elements are significant differences in iron ore among different countries. Polarizing microscopy investigation shows that there are great differences not only in mineral types but also in other aspects (e.g., accessory mineral types, accessory mineral content, and structure). These differences can be used as proxies for the identification of iron ore origin. Finally, in situ major and trace elements of magnetite were used to distinguish the genetic types of iron deposits. The magnetite deposits from Burma and Laos are skarn type, while those from Australia are mainly BIF type. In this study, multiple techniques were used to characterize the differences in element content, mineral facies composition and mineral-forming environment of iron ore samples and to comprehensively analyze the mineralogical characteristics of iron ore samples from different countries. These differences are of great significance for the identification, quality control and origin of imported iron ore resources.

Keywords

• iron ore
• mineral phase analysis
• trace elements
• la-icp-ms
• genetic type of deposit