Pentlandite and violarite in the Notträsk deposit, northeastern Sweden

Pyrrhotite mineralogy of the Notträsk deposit, northeastern Sweden

“…One might even add that in this type of mineralization relative paucity of monoclinic pyrrhotite in bulk intermediate pyrrhotite might be an indicator of equal paucity of the economically interesting pentlandite. This discussion is consistent with our previous conclusions regarding the origin of the present composition of the Nottrask mineralization (Arvanitidis & Rickard 1980). We suggested that the Nottrask mineralization obtained much of its present constitution at relatively low temperatures, at least below 300°C.…”

“…Arvanitidis & Rickard (1980) noted that pentlandite exsolution from the original monosulfide solid solution (tnss) occurred at temperatures below 300°C. The separation of pentlandite moves the nzss composition toward iron monosulfide.…”

“…The sulfide mineralization consists of major pyrrhotite with minor chalcopyrite, pentlandite and violarite and rare cubanite, mackinawite and gersdorffite. Pentlandite-violarite relationships in the deposit have been described by Arvanitidis & Rickard (1980).…”

The effect of crystallochemical peculiarities of nickel sulphide minerals on flotation of copper–nickel ore

“…One of the probable mechanisms of violarite formation over pentlandite is its electrochemical oxidation under supergenic conditions (Thornber, 1983). During violaritization, the metal losses occur nonuniformly: the first to be lost is iron while the cobalt content remains practically the same (Arvanitidis and Rickard, 1979). At the same time, there is evidence about violarite formation under hypogenic conditions as well, up to 461 jC (Crag, 1971).…”