High form of pentlandite and its thermal stability

  title={High form of pentlandite and its thermal stability},
  author={Asahiko Sugaki and Arashi Kitakaze},
  journal={American Mineralogist},
  pages={133 - 140}
Abstract The high-temperature form of pentlandite (Fe4.5Ni4.5S8) was found to be stable between 584 ± 3 and 865 ± 3 °C, breaking down into monosulfide solid solution and liquid at the later temperature. The phase is unquenchable and always displays the X-ray pattern of pentlandite (low form) at room temperature. High-temperature X-ray diffraction demonstrated that the high form has a primitive cubic cell with a = 5.189 Å (620 °C) corresponding to a/2 of pentlandite. The high-low inversion is… 

Phase Relations in the Fe–ni–s System from 875 To 650 °c

Abstract High-form pentlandite of composition Fe 4.93 Ni 4.06 S 8.01 first crystallizes by peritectic reaction between liquid and monosulfide solid-solution at 870 ± 3 °C (865 ± 3 °C for high-form

A kinetic study of the exsolution of pentlandite (Ni,Fe)9S8from the monosulfide solid solution (Fe,Ni)S

Abstract The kinetics of the exsolution of pentlandite from the monosulfide solid solution (mss) have been investigated using a series of anneal/quench and in situ cooling neutron diffraction


An elongate field of high-form pentlandite solid-solution, Fe 5.65 Ni 3.35 S 7.85 , β 2 (Ni 4± x S 3 ), occurs in the system Fe–Ni–S at 650°C. This solid solution coexists with monosulfide

The Occurrence and Origin of Pentlandite-Chalcopyrite-Pyrrhotite Loop Textures in Magmatic Ni-Cu Sulfide Ores

Pentlandite is the dominant Ni-hosting ore mineral in most magmatic sulfide deposits and has conventionally been interpreted as being entirely generated by solid-state exsolution from the

Structure and Reactivity of Terrestrial and Extraterrestrial Pyrrhotite

Pyrrhotite (Fe1-xS) is a non-stoichiometric iron monosulfide common in terrestrial rocks, ore deposits, and many extraterrestrial materials. The non-stoichiometry due to metal vacancies relates to a

Phase equilibria in the system Fe-Ni-S at 500°C and 400°C

Phase equilibria in the system Fe-Ni-S were investigated by dry synthesis at 500°C and 400°C using three elements (Fe, Ni and S) and two synthetic sulfides (FeS and NiS). Phase diagrams of this

Fe0.45S0.55-Ni0.66S0.34 section of the Fe-Ni-S phase diagram

The Fe0.45S0.55-Ni0.66S0.34 section of the Fe-Ni-S phase diagram was constructed using thermal analysis, microscopy, X-ray powder diffraction, and electron probe microanalysis data obtained for the

The section of the Fe–Ni–S phase diagram constructed by directional crystallization and thermal analysis

A nontrivial polythermal cross-section through the Fe–Ni–S phase diagram was plotted using a combination of directional crystallization and DTA methods. The crystallized sample was grown from the



The central portion of the Fe-Ni-S system and its bearing on pentlandite exsolution in iron-nickel sulfide ores

A detailed study of the central portion of the Fe-Ni-S system between 600 degrees and 250 degrees C has been conducted by means of silica-tube techniques. Particular emphasis has been placed on

Cattierite and Vaesite: New Co-Ni Minerals from the Belgian Congo

The group which includes CoSr, NiSz, and FeSz forms an isostructural series following the pyrite lattice. Heretofore, the formation of the artificial end members of the series has been established,

Kamacite and taenite superstructures and a metastable tetragonal phase in iron meteorites.

Kamacite and taenite in iron meteorites have cubic superstructures in which the unit cell edges are respectively three times and two times those of the disordered phases. Certain iron meterorites

Thermodynamics and Phase Relationships of Transition Metal-Sulfur Systems: II. The Nickel-Sulfur System

The thermodynamic activity of sulfur in the β1-Ni3S2, β2-Ni4S3, γ-Ni6S5 and δ-NiS phases was determined as a function of composition over the temperature interval, 823 to 1023 K, using a gas

Economic Mineral Deposits

This book serves as a complete, yet concise introduction to heat, for students in engineering. chemistry, physics, astronomy, or general science who have had the beginning college course in general

The Ni-S System and Related Minerals

Thermal stability of pentlandite

The thermal stability of pentlandite was studied by quenching, differential thermal analysis, and high-temperature X-ray diffraction experiments. Rigid silica tubes were employed as reaction vessels,

Thermal Expansion of the Pentlandite Structure