History Deposits of micaceous hematite ore near Williamstown, SA were formerly exploited for iron flux, and, more recently for cement and paint filler material. However, the mine had to be closed due to flooding of the site under the present South Para water reservoir. Other deposits in the same general area were taken up under Mineral Lease and a company, Micor Pty Ltd, was formed in 1965 to exploit the deposits. Previous work done at laboratory and pilot scales had shown that beneficiation of the ore by froth flotation using fatty-acid collectors produced concentrates closely approximating British and American Standards for paint pigment material. Objectives Further investigation was desired to determine: a. the physical and chemical properties of material which should be aimed for in any beneficiation process, to compete with currently marketed pigments for paints, concrete masonary and ceramic ware b. the quality requirements for other uses, such as welding-rod coatings and ceramic magnet powders, and c to produce bulk samples of material as indicated by “a” and “b” for consumer evaluation. Summary of Work Done Laboratory milling and micronising of the Malcolm Creek ore, and its beneficiated by flotation, gave powders of high specific surface area. The powder was of a plum red colour, and the colour of synthetic red iron oxide could not be matched by roasting Malcolm Creek material in an oxidizing atmosphere. Reduction roasting, howeve,r gave a black powder closely approaching the colour of a synthetic black iron oxide sample of imported origin. Samples of prepared natural colour and black pigments were submitted to ceramic and concrete manufacturers. Laboratory and pilot scale dry-milling and size classification tests undertaken on this ore failed to produce the desired product grade. The wear on milling equipment was excessive, due to the abrasive nature of the siliceous fraction of the ore. Further beneficiation of dry-milled and size classified ore by flotation proved difficult, and low-grade concentrates were produced from continuous pilot scale operation. Wet milling and size classification of the ore provided a suitable feed for flotation, and satisfactory concentrate grades and recoveries were obtained in continuous operation. A bulk sample of approximately 9 tons of concentrate containing 82.9% Fe2O3 was produced for consumer evaluation. The highest concentrate grade produced in one eight-hour period from continuous operation was 93.7% Fe2O3; calculated recovery at a concentrate grade of 88.5% Fe2O3 was 91%. Conclusions The following conclusions were drawn from the test work: 1. A micaceous hematite concentrate can be produced at satisfactory recovery from ground ore by froth flotation. 2. The grade of concentrate obtainable from a feed containing approximately 55% Fe2O3 is up to 95% Fe2O3, and thus meets the grade requirements of material for welding rod coatings and structural paint filler. 3. Further size classification or size reduction of flotation concentrate may be required to meet the size specifications of paint filler grade material: however, the bulk sample produced meets the chemical and other physical requirements of most known paint filler specifications. 4. Production of a black pigment of high surface are from a micaceous concentrate is feasible by reduction roasting and fine size reduction; however, the density of colour obtained will not match that of synthetic oxide powders of much higher purity. Recommendations It is recommended that portions of the bulk micaceous hematite concentrate sample produced be submitted to consumers for evaluation. Should the market demand for such material warrant the establishment of a treatment plant, the basic flowsheet is recommended. The data obtained from the pilot scale operations described in this report can be used for specification of some of the major items of plant equipment.