Minerals identify

Know how to recognize them



The thiospinel group is a group of sulfide minerals with a general formula AB2X4 where A is nominally a +2 metal, B is a +3 metal and X is -2 sulfide or similar anion (selenide or telluride). Thio refers to sulfur and spinel indicates their isometric spinel

As the chalcogens S, Se and Te are less electronegative in these materials is generally more covalent than in the oxospinels. Some are (magnetic but others display, at times complicated, metallic behavior, often coupled with equally complicated magnetic properties. The assignment of oxidation states is also not always as straightforward as in the more ionic oxocompounds, as is shown in the case of carrollite.

Group members include: * Cadmoindite - CdIn2S4 * Carrollite - CuCo2S4 * Fletcherite - Cu(Ni,Co)2S4 * Greigite - Fe2+Fe3+2S4 * Indite - FeIn2S4 * Kalininite - ZnCr2S4 * Linnaeite - Co2+Co23+S4 * Polydymite - Ni2+Ni23+S4 * Siegenite - (Ni,Co)3S4 * Tyrrellite - Cu(Co,Ni)2Se4 * Violarite - Fe2+Ni23+S4