The deposit type is lateritic bauxite derived from the weathering of aluminous sediments in a tropical to sub-tropical environment. The Bauxite Hills area forms part of the Weipa Plateau and is underlain by rocks of the Carpentaria Basin. The oldest rocks intersected by drilling in the area are grey-black marine shales, which have been assigned to the Cretaceous Rolling Downs Group. This is up to 250 m thick and is underlain by sandstones of the Helby Beds. These rocks are a source of artesian water. The bauxite deposits generally consist of a single bauxite layer, 0.5 m – 3 m thick, that is underlain by a kaolin horizon. The bauxite deposits are overlain by lateritic overburden and topsoil. Under the bauxite there is often a cemented ironstone and a kaolin clay layer. Kaolin, sandy clays and minor quartz sand deposits occur beneath the bauxite layer and extend beyond the bauxite areas, beneath the Namaleta Creek flood plain. Bauxite occurs over the majority of the plateau areas. It is pisolitic in form and is generally covered only by a thin layer of soil, but in the western parts of the project area bauxite is sometimes found beneath sand dunes at depths of up to 6 m. The bauxite passes down into an iron rich horizon (ferricrete) and then into mottled, bleached Bulimba Formation sandy clays. Bauxite pisoliths generally form 55-80% of high-quality bauxite, with the remainder being sand, silt and clay. The pisoliths are well rounded, and generally 5 to 20 mm in size, alt ........

The Bauxite Hills Mine is a simple mining operation. Free-dig bauxite is mined by front-end loaders and then trucked on dedicated haul roads to the port infrastructure.

The bauxite is then screened to a maximum product size of 100mm and fed into the Barge Loading Facility (BLF) and into barges.

Tugs tow the barges down the Skardon River and out to an anchorage point beyond the river mouth where ocean-going vessels are loaded with bauxite.

Mining operations are undertaken in the dry season only; a notional 8-month period from April to November.

Metro Mining’s Scania fleet consists of nine V8 powered trucks, one R-620 and eight R-730s, which work around the clock day-in, day-out.

The mining of bauxite at Bauxite Hills commenced in April 2018. The operation is a conventional truck and front-end loader process. No blasting is required. Minor ripping is undertaken where cemented pisolitic bauxite is present. Overburden is removed by bulldozers or graders and placed in mined-out areas. The learnings from the existing operation have been considered in this updated Resource estimate. Mined areas have been excluded from this resource estimation.

Bauxite ore is mined using front-end loaders as per the existing operation. Waste will be stripped by dozers and placed on the mined-out floor by an excavator and truck fleet to establish rehabilitation. Once the bauxite ore is exposed the FEL will mine the bauxite down to the ........

The ore has been considered a DSO (direct shipping ore).
Screening is undertaken to remove oversize. The orebody is known to contain a portion of cemented bauxite, estimated to make up 5% of the total reserve. The cemented bauxite does not break up as easily as the non-cemented bauxite. Oversize cemented bauxite is crushed and re-fed over the screen until it passes.

The ore has been considered a DSO no beneficiation as such is undertaken.