Mineral phase
- IMA name
- Pyrrhotite
- Class
- non-silicate mineral
- Compound type
- sulfide
- Comments
- magnetic, depend on the number of Fe vacancies in the crystal structure - Polytypes: -4M: Fe7S8 (monoclinic, C2/c), -5H: Fe9S10 (orthorhombic, Cmca), -6M: Fe11S12 (monoclinic, Cc), -7H: Fe9S10 (hexagonal, P6(3)/mmc), -11H: Fe10S11 (hexagonal), Troilite: FeS (hexagonal, P6(3)/mmc)
- Formula
- $Fe_{1-x}S \ \ \ \ $ where $x=0-0.17$
- Chemical formula
- Fe(1-x)S
- Elemental formula
- (Fe)0.83-1 S
- Isotope mixture type
- terrestrial abundance
| Formula | Name | Family | Number min-max | Isotope mole fraction | State | Relevance | |
|---|---|---|---|---|---|---|---|
| $Fe$ | Iron | element | 0.83 - 1 | constituent element | main | ||
| $S$ | Sulfur | element | 1 | constituent element | main |
- Composition comments
- Polytypes: -4M: Fe7S8 (1-x=0.875), -5H: Fe9S10 (1-x=0.90), -6M: Fe11S12 (1-x=0.917), -7H: Fe9S10 (1-x=0.90), -11H: Fe10S11 (1-x=0.909), Troilite: FeS (1-x=1) - Common impurities: Ni, Co, Cu
Strunz
- Class
- sulfides - sufosalts (02)
- Division
- metal sulfides, M:S = 1:1 (and similar) (02.C)
- Family
- With Ni, Fe, Co, PGE, etc. (02.CC)
- Code
- 02.CC.10
Dana
- Major class
- sulfides (II)
- Class
- sulfides - including selenides and tellurides (02)
- Type
- where Am Bn Xp, with m:p=1:1 (02.08)
- Group
- -Pyrrhotite- group (02.08.10)
- Code
- 02.08.10.01
- End-members
- Members
-
- Pyrrhotite-4M (Fe7S8 (x=0.125))
- Pyrrhotite-5H (Fe9S10 (x=0.1))
- Pyrrhotite-6M (Fe11S12 (x=0.083))
- Pyrrhotite-7H (Fe9S10 (x=0.1))
- Pyrrhotite-11H (Fe10S11 (x=0.091))
- Troilite (FeS (x=0) (specific mineral))
- Phase type
- crystalline
- Crystal system
- monoclinic
- Crystal class
- prismatic
- Crystal class symbol
- 2/m (C2h)
- Crystal spacegroup
- C2/c
- Molar mass
- 78.42 - 87.91 $g/mol$
- Density
- 4.58 - 4.65 $g/cm^3$
- State NTP
- solid
- Refringence type
- unknown
- Refringence sign
- unknown
- Pure color
- brown
- Color
- bronze, bronze red, dark brown
- Diaphaneity
- opaque
- Luster
- metallic