Averievite: a spin-1/2 copper oxide kagome antiferromagnet

The synthesis of herbertsmithite has led to a revolution in the field of quantum magnetism. This Cu²⁺-hydroxide mineral constituted the first realization of the quantum spin liquid state in a spin-1/2 system with kagome geometry, a long sought holy grail in Condensed Matter Physics. Ever since, other candidate materials have been intensively searched for. Herbertsmithite taught us that the conditions required for a quantum spin liquid to form are often found in Nature. Within this context, we have identified and synthesized averievite, an oxide mineral discovered in a volcano in the Kamchatka peninsula. Composed of Cu²⁺ kagome layers sandwiched by Cu²⁺-V⁵⁺ honeycomb layers, partial substitution with Zn leads to spin liquid behavior, in analogy to herbertsmithite.