The Wessels mine is situated in the Northern part of the Kalahari Manganese field.

Mineralisation of the Kalahari Manganese field is developed in three braunite-kutnahorite lutite layers interbedded with iron formation in the Hotazel Formation of the Palaeoproterozoic (2400 to 2100 Ma) Transvaal Sequence which was deposited within an intracratonic basin on the Kaapvaal Craton. The relatively flat lying, concealed, mineralised, Hotazel Formation units of the Kalahari manganese field covers an area of some 30 x 10 km.

The base of the Hotazel Formation consists of a bright-red banded iron formation bed (varying from massive to fine-grained specularite and/or euhedral magnetite cystals) overlying volcanic glass breccias and lavas of the Ongeluk Formation. The banded iron-formation units grade into microcrystaline kutnohoritic ovoidrich braunite rock. The kutnohorite in this area is concentrated in ovoids, which represent partially compacted, early diagenetic concreations in hematite and braunite rock. The braunite rock bed of the lower section of the lowest of the three sedimentary cycles present in the Hotazel Formation, is between 5 and 45m thick. This is the major ore unit of the Kalahari manganese field with a manganese content varying between 20 and 48 weight percent. The middle manganese-bearing unit (cycle 2) is a maximum of 2m thick and in not economically viable. The top manganese ore body was mined in previous years. It rarely exceeds 5m thickness. Grey hematitic and manganese minnesotaite rocks are found between the lower and the middle maganese ore bodies.

The Wessels Mine is seperated into three underground areas. The first, the central-southern area, is particularly rich in carbonates, primarily manganoan calcite, kutnahorite and rarely rhodochrosite. The second, the north-western area, in known for its sturmanite, gaudefroyite and sugilite. Finally the third area, the central eastern area, has sugilite, andradite, inesite, hydroxyapophyllite, ruizite, barite and celestine.

Wessels is an underground bord and pillar operation with a current capacity of approximately 1.2 Mtpa of ROM production (100 per cent basis).

Primary crushing of ore takes place underground, while secondary crushing forms part of the surface operations. ROM ore is washed and screened on the surface to produce various quality products.