The role of orientation of crystal lattice on the development of bacterial leaching patterns on pyrite single crystals

To investigate the influence of orientation of crystal lattice on the bacterial leaching of pyrite crystals, single crystals of 100, 111 and 110 plane orientations were used for the study. Experiments were carried out in the presence of a Thiobacillus ferrooxidans culture. The different corrosion patterns observed on the surfaces of the bioleached samples suggests a variation in cell-surface interaction from one crystal plane to the other. The surface corrosion patterns generally reflected the influence of the symmetrical arrangement of the atomic planes in the lattice on which they formed. The results indicate that the surface properties of mineral sulphides may control the evolution of corrosion patterns and consequently the initial oxidation process in acid bacterial leaching