Nickel Minerals and Ores

The ionic radius of divalent nickel (Ni + 0.69 A) is similar to that of divalent iron (Fe 0.77 A) and magnesium (Mg 0.71 A). Therefore the three elements substitute for one another in minerals. 

There are two main types of nickel ore. Sulfide ores occur as massive ore bodies or impregnated in cracked or fragmented rock (breccia). Nickel sulfides and copper sulfides are both present and typical percentages are 1-2% Ni and 3% Cu. The sulfide ores often contain cobalt, and sometimes platinum metals as well. 

The most important nickel sulfide mineral is pentlandUe (Ni,Fe) Sg a mineral that is formed at great depth in the interior of the earth by magmatic activity or by hy- 

The other type is oxide ores, especially the laterite ores. Garnierite and nickeliferous limonite are important components of these. In the concentration zone, where garnierite has been formed, the nickel content can be 2-3.5%. 

Theme Nickel, p. 38. Geological Survey of Sweden. With permission.) 

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