1. About zinc

1.1 In the wild

Zinc is present in varying quantities in numerous ores and rocks. The most widespread mineral in the lithosphere and the most widely used for metal production is zinc sulfide, known as blende or sphareliite (ZnS), which has a cubic structure. It may contain metallic impurities, such as iron (dark blends), cadmium, silver... Marmatite ((Zn, Fe)S) contains up to 14% iron. In natural environments, blende is associated with other sulfides, such as galena (lead sulfide: PbS).

Zinc is the world's fourth most important metal after iron, aluminium and copper. Over the past three decades, the Western world has accounted for most of the growth in zinc mining and metallurgical production, but other countries such as China are now taking up the slack. Buoyed...