Leaching Metals from Phyllosilicate Ores

Phyllosilicate minerals are important ores of V, Zn, Ni, and sometimes Cu. This paper uses phyllosilicate crystal chemistry, leaching experiments, and transmission electron microscopy to examine metals’ three distinct modes of occurrence and leachability in these ores. (1) Adsorbed metals can be liberated via exchange with solution cations, depending on chemical conditions and phyllosilicate type. (2) Crystallographically contained metals are partially leachable, typically at elevated temperatures, if they are in octahedral or higher coordination. (3) V, Ni, Cu, and possibly other metals, form discrete nanometer-scale inclusions within phyllosilicates whose leachability is mostly controlled by their mineralogy, not the phyllosilicate host’s.