Weda Bay Ni rich laterites developed on dunite and harzburgite.

The Weda Bay laterite profile, developed during the Cenozoic, is bout 10 m thick, of which 8 m is mineralised with grades in excess of 1% Ni. The profile displays the general layered characteristics of tropical laterites elsewhere. However, the ferricrete capping common to many tropical laterites has been removed by erosion leaving only relict ironstone cobbles and, more commonly, small pisolites that are incorporated into the upper part of the profile (Cock and Lynch, 1999).

Below the overburden horizon, a limonite occurs with > 55% Fe2O3 and no relics with the pristine textures of the ultrabasic rocks still in place. A certain amount of recognizable grains (quartz, altered serpentine clasts, manganese oxides) are visible within a matrix, brown red in colour, dominated by iron oxy-hydroxides. At the basis of this horizon, a transition zone (ferruginous saprolite) is found, and is characterized by more abundant clasts of saprolite within the fine grained goethite matrix (ferruginous saprolite, 25 to 50% Fe2O3 (Cock and Lynch, 1999).

Below the ferruginous saprolite, a saprolite horizon (hydrous Mg silicate zone) is characterized by a non-ferruginous texture (< 15% Fe2O3), is green-brown in colour and may be rather soft. The lower saprolite horizon contains fresher green serpentinite and clasts of bedrock.

The mining operation is in open-pit mines.

During mining, on the basis of the mining plan defined in agreement with the supervisory authorities, the run-of-mine volumes extracted are separated according to their future use. Firstly, the topsoil is stored separately in the immediate vicinity of the pits, in order to be reused to rehabilitate and revegetate the mine after exploitation. Then the waste which has no industrial use, is stored in waste dumps which are rehabilitated once completed.

The three Rokbak RA40 haulers entered Weda Bay in February 2022.

Required to move around 450 tonnes of biomass and quarry materials in a single day. The haulers are tasked with removing overburden and providing mine development. Every full-capacity payload sees each RA40 transport overburden two-kilometres to a project access road and biomass dump for disposal.

- subscription is required.