| Pentlandite | |
|---|---|
 3.1 × 2.6 cm mass of pentlandite with some pyrrhotite | |
| General | |
| Category | Sulfide mineral |
| Formula (repeating unit) | iron nickel sulfide: (Fe,Ni)9S8 |
| IMA symbol | Pn[1] |
| Strunz classification | 2.BB.15a |
| Dana classification | 2.7.1.1 |
| Crystal system | Isometric |
| Crystal class | Hexoctahedral (m3m) H-M symbol: (4/m 3 2/m) |
| Space group | Fm3m |
| Unit cell | a = 9.928 Å, Z = 4 |
| Identification | |
| Formula mass | 771.94 g/mol |
| Color | Yellowish bronze |
| Crystal habit | Hexoctahedral rare; massive to granular |
| Cleavage | Absent – octahedral parting on {111} |
| Fracture | Conchoidal |
| Tenacity | Brittle |
| Mohs scale hardness | 3.5–4 |
| Luster | Metallic |
| Streak | Light bronze-brown[2][3][4][5] Greenish black[6][7][8] |
| Diaphaneity | Opaque |
| Specific gravity | 4.6–5.0 |
| Density | 4.6–5 g/cm3 |
| Fusibility | 1.5–2 |
| Other characteristics | Becomes magnetic upon heating |
| References | [9][2][3][4][5][6][7][8] |
Pentlandite is an iron–nickel sulfide with the chemical formula (Fe,Ni)9S8. Pentlandite has a narrow variation range in nickel to iron ratios (Ni:Fe), but it is usually described as 1:1. In some cases, this ratio is skewed by the presence of pyrrhotite inclusions. It also contains minor cobalt, usually at low levels as a fraction of weight.
Pentlandite forms isometric crystals, but it is normally found in massive granular aggregates. It is brittle with a hardness of 3.5–4 and specific gravity of 4.6–5.0 and is non-magnetic. It has a yellowish bronze color and a metallic luster.[10]
Pentlandite is found in abundance within ultramafic rocks, making it one of the most important sources of mined nickel.[11] It also occasionally occurs within mantle xenoliths and "black smoker" hydrothermal vents.[12]
- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ a b Handbook of Mineralogy
- ^ a b Mindat.org
- ^ a b Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., Wiley, p. 280-281 ISBN 0-471-80580-7
- ^ a b Mindat.org - Forum
- ^ a b Webmineral.com
- ^ a b "Pentlandit" (in German).
- ^ a b Schumann, Walter (1991). Mineralien aus aller Welt (in German) (2nd ed.). BLV. p. 224. ISBN 978-3-405-14003-8.
- ^ Mineralienatlas
- ^ "Pentlandite". www.mindat.org. Retrieved 2023-02-20.
- ^ Kerfoot, Derek G. E. (2005). "Nickel". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a17_157. ISBN 978-3527306732.
- ^ "Pentlandite" (PDF). Handbook of Mineralogy.