This paper describes the steel sharpening practices adopted by Wiluna Gold Mines Ltd. in its rock-drill steel sharpening shop at Wiluna. From the steel metallurgists' viewpoint the methods are not strictly in accord with theory, but they are a close approximation and the results obtained-quality of bit at a reasonable cost-justify the present practices which, however, are being constantly improved as new machines and technique are developed. SHOP. The plan, Plate I., shows the general layout of the drill steel sharpening shop, together with the disposition of the machines used in producing finished bits and shanks. The building housing the equipment is a steel and galvanised iron structure. The front of the shop is open for the full length of the building and to a height of 8 ft. The other walls are fitted with adjustable shutters.' Under these conditions the shop is well lighted by natural means and at the same time well ventilated,- a necessary requirement in a climate where for several months in the year the shade temperature exceeds 100 F. To assist the operator to determine the correct forging and tempering heats, the shop is equipped with magnetic indicators and colored charts. The plan, Fig. 1, shows the construction of the magnetic indicator. The color chart is used in conjunction with a piece of 4-in. pipe, in which the steel is placed to enable the operator to check the heat against the chart in a constant light. With a little experience the operator is soon able to judge the temperatures within close limits. The floor of the shop is formed of concrete and, instead of installing truck lines in the building, the steel is handled on trucks fitted with 10-in. diam. wheels with flat tyres 3 in. wide.