ISSN:
1432-1866
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
Notes:
Abstract Pentlandite has a wide compositional range in the Fe-Ni-Co-S system and the Fe-Ni-S system. The metal : sulfur atomic ratio is approximately 9 : 8. The Co content of pentlandite from the Kamaishi ore deposit and one from the Outokumpu ore deposit (Knop et al. 1965) varies from a Co-free to nearly a Co9S8 composition. Pentlandite forms a complete solid solution between (Fe, Ni)9±x S8 and Co9±x S8 in the 600°–300°C temperature range. On the other hand, it is presumed that the pentlandite solid solution decomposes into two fields toward the (Fe, Ni)9S8 and Co9S8 members at 200°C. The field of solid solution at 500°C is the most extensive and includes all of the other solid-solution fields. The metal : sulfur ratio of the solid solution varies systematically, i.e., the Fe-rich field sinks toward the Fe-Ni-Co plane away from the M9S8 section, and contrarily the Ni-rich field shifts toward the sulfur apex. The d 044 value decreases with increasing S, Ni, or Co contents in pentlandite. The Kamaishi pentlandites, Iwate Prefecture, Japan, lie within or close to the solid-solution field at 300°C, showing a very good correlation with the Co : Ni ratio of the homogeneous natural pyrrhotite phase.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00199797
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