A representative selection of rock types obtained in the cores of the DDH1 and DDH2 iron ore exploration holes was made with a view to studying the mineralogy, the lithology and any microstructures of interest present in the formations intersected. A considerable amount of useful data was obtained by the thin and polished section examination of these samples. The petrographic survey was necessarily restricted because of the vast amount of material delivered by more than 2800 feet of diamond drilling, but the information which follows constitutes sufficient detail from a practical viewpoint without entering into too academic a discussion on the subject. The several formations are discussed in turn, same detail is given about the nature and distribution of uncommon amphiboles and pyroxenes, the mineralisation sequence is presented, and the origin of the magnetite is discussed.