This report is the result of eighteen months’ field work by a small party. It presents a general picture of the geological and structural setting of the ore deposits of the Middleback Ranges. The rock types within the area described in detail and the rock structures are discussed. The hematite quartzites are considered to be of sedimentary origin and the structural interpretation is based upon this assumption. The conclusion is reached that the ore-bodies were formed by the desilicification and iron enrichment of hematite quartzites by descending solutions. Manganese moved into the ore-bodies by similar processes, but its source is not known. The ore-bodies were formed at or just prior to the time of deposition of the Corunna Hills rocks. In addition to recording all the available surface details on and adjacent to the company’s leases, this report incorporates all past prospecting data. The report presents complete and should be kept up to date as work proceeds. All the ore-bodies are shown on plans with a scale of 100 feet to one inch and five foot contours. Gross sections at 100-feet intervals are shown for all the ore-bodies. A review of the prospecting methods is given and the relative efficiencies are compared. Criticism is directed at the past methods of supervising and recording prospecting activities. The fault is traced to the use of inadequately trained cadets with insufficient guidance and supervision. Recommendations are made for the revision of the present unsatisfactory method of supervision and suggestions are offered for raising the standard of the company’s records. Each ore-body is described and the prospecting necessary to prove the ore is outlined generally. In addition, a few general notes on future development are submitted.