Effect of mineralogy and texture on the strength of iron ore

A preliminary investigation on three types of iron ore from the same deposit was carried out. Major
minerals in all the three ores are dense martite, microplaty hematite, vitreous goethite, ochreous goethite
at varied proportion whereas kaolinite and quartz occur in minor to trace amount. There is a textural variation with micro-porosity. The strength is the maximum (674 kg.f/cm2) in the ore dominated by dense martite and pseudotachylite whereas moderately low (254 kg.f/cm2) in the ore with micro-platy hematite
and extensive micro-porosity, and is the lowest (157 kg.f/cm
2) for the ore dominated by goethite. Presence
of pseudotachylite, reported for the first time, in dense martite iron ore possibly provides additional
strength to the latter.