The mineral chemistry, ore textures and styles of mineralisation are discussed for each ore mineral. Both, the mixed sediment-/volcanic-hosted non sulphide ore body and the remnants of volcanic-hosted sulphide mineralisation are known from abundant drill core and recently exposed non-sulphide mineralisation in the open pit. Remnants of a primary sulphide mineralisation are mainly preserved in the felsic metavolcanic rocks and their hyaloclastic eqivalents, which structurally underlie the central portion of the supergene ore body at depth.

The felsic metavolcanic rocks are also exposed some hundreds meters west of the Skorpion open pit, displaying disseminated pyrite mineralisation or forming gossans. The most famous gossan, which is located west of the Skorpion ore body, is the so called 'discovery outcrop'.

Within the footwall of the Skorpion non-sulphide zinc ore body disseminated to semi-massive primary pyrite sphalerite mineralisation has been intersected at a depth of 250 m and 300 m, respectively, which features a 25-m-wide zone grading 0.6 % Zn and 0.35 % Cu.

For completeness it has to be mentioned that some minor primary sulphides have been found in metasiliciclastic rocks but also in marble in the northern extension of the Skorpion ore body about 1.5 km north of the Skorpion open pit, e.g. borehole SD104, at a depth between 550 m and 700 m in unaltered fresh equivalents of the Skorpion metasiliciclastic host rocks and marble, respectively.

The Skorpion mine and refinery is located in the Karas region of southern Namibia, comprising an open pit mine. The Skorpion mine produces only high-grade, high purity SHG zinc ingots that are registered on the
LME.

The ore deposit of Skorpion Zinc is unique as it is a primary oxide/silicate/carbonate zinc deposit, which cannot be concentrated by flotation. In this process, mined ore is crushed, homogenised and milled before acid leaching in agitated tanks at the refinery. Clarified liquor is purified by solvent extraction and zinc is electrolytically plated on to aluminium cathodes. Zinc is periodically stripped from these cathodes before being melted and cast as ingots for export.

The absence of sulphur offers an advantage in that no sulphur or sulphuric acid disposal is required. The ore is leached directly in sulphuric acid to produce zinc sulphate. It is not possible to directly electrowin zinc from the sulphate solution due to the high chlorine and florine levels, and other impurities contained in the Skorpion Zinc ore, which cause anode and cathode corrosion, and cathode stripping problems. Solvent extraction provides a buffer against chlorine and florine, and effectively prev ........