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• Strength at coarse sizes directly related to vertical position in deposit. • Limited correlation between strength at coarse sizes and grindability. • Evidence of gangue concentration in intermediate sizes for selected ore types. Low-grade iron ore deposits in Brazil are typically represented by rocks called itabirites. These deposits contain ores with different characteristics, which present varying degrees of weathering, with direct implications in iron contents, liberation characteristics and comminution response. This work analyzes the five main ore types or lithologies contained in the Serra do Sapo deposit, as part of the Minas-Rio mining complex (near the city of Conceição do Mato Dentro, Brazil). Besides detailed chemical and mineralogical composition, liberation characteristics of the ore types have been analyzed by scanning electron microscopy and QEMSCAN. Samples were also subjected to point-load and abrasiveness tests as well as batch grinding tests. It is evident that at coarse sizes the ore types present significantly different strengths and abrasiveness, with values decreasing, as expected, with increasing degree of weathering. However, such differences partially disappeared as comminution progressed to finer sizes. Amenability of the different ores to slimes generation also varied, with weathered ores presenting significantly higher values. Grade by size deportment results show that selected ore types offer opportunity for early gangue (silica) rejection prior to the grinding stage. [ABSTRACT FROM AUTHOR]