Ravensthorpe Nickel Operations (RNO) consists of several discrete nickel laterite deposits.

The mineral resources defined at the Halley's, Hale-Bopp, Shoemaker-Levy, Nindilbillup and Shoemaker-Levy North nickel laterite deposits have developed over Archaean ultramafic rocks through prolonged deep weathering. Sub-horizontal tabular zones containing residual and supergene accumulations of nickel, cobalt, manganese and iron have developed in association with extensive leaching of principally magnesium.

The majority of nickel mineralisation in the RNO deposits is hosted in the goethite/limonite zone, whilst the upper levels of the saprolite zone is also commonly well mineralised. In all RNO deposits, nickel mineralisation forms as a blanket beneath barren surface units whilst cobalt mineralisation occurs mainly in a narrow zone generally towards the top of the nickelenrichment zone in association with manganese accumulation. It is often centred around the redox boundary in the limonite zone, recognised by an accumulation of manganese enrichment.

Operations at Ravensthorpe involve open pit mining and beneficiation of nickel laterite ore.

All mining activities will take place in the three mining areas, each of which has been split into smaller stages. The current mining activities in Halleys involve a conventional Drill/Blast and Load/Haul operation. There is up to 40% free diggable ore and waste to be mined over the life of mine. All remaining ore and waste requires drilling and blasting.

The mining contractor mobilized and commenced mine production early in the first quarter of 2020. On the process plant, commissioning works and recruitment of operations personnel are planned to continue to ramp up ahead of expected first nickel and cobalt production during the quarter. The first two shipments of sulphur, a critical process reagent, were received in January 2020.[12.31.2019 MDA, p. 27]

Beneficiation
Nickel and cobalt values are enriched in the fines fractions of both the limonite and Saprolite ores, and the beneficiation process consists of rejecting the principally siliceous coarse fractions using conventional wet ore sizing equipment. Typical mass rejections of 60-70% are achieved at a nominal nickel recovery of 60-65%.

Crushed ore to each Beneficiation circuit is recovered from its respective reclaimer stockpile. Both feeds direct the crushed ore to a drum scrubber, where loose ore agglomerates are broken up and dispersed, and any loosely attached mineralisation is scrubbed from the siliceous gangue. The scrubber product is treated through a combination of screening and hydraulic classification to recover the nickel and cobalt values, which are now concentrated in the -100µ fraction. The +100µ material is discarded to a reject stream which is mechanically transported to a dump.

Limonite beneficiated products are treated through Pressure ........