Mössbauer and X-ray Diffraction Spectroscopy of High-Iron Bauxites from Kazakhstan

The bauxite ores of Kazakhstan were analyzed using Mossbauer spectroscopy, X-ray diffraction and an X-ray fluorescence analysis. Experimental data on the structural-phase composition of bauxites were obtained, and the features of the iron-bearing minerals within them were revealed. The studied bauxites were high in iron. The magnetic part of bauxite was mainly represented by aluminohematite with a concentration of CAl = 3.34-5.73 at.%, alongside goethite in small amounts. The predominant phase in the bauxite samples was the alumina-bearing mineral gibbsite with a well-crystallized monoclinic lattice. The main siliceous mineral of bauxite is kaolinite, which showed distorted octahedral positions in a number of samples. Siderite amounts were found to vary in the range of 0-15 at.% in the present iron-bearing minerals. Ilmenite was also present in the bauxite of some deposits; anatase was found in all bauxites and was the final product of ilmenite decomposition in the weathering crust.

Automated summary

The bauxite ores of Kazakhstan were analyzed using various techniques, revealing the structural-phase composition and iron-bearing minerals within them.