File:Pyrrhotite-Sphalerite-Quartz-195225.jpg · Wikimedia Commons · See Wikimedia Commons
pyrrhotite
Sign in to savePyrrhotite (pyrrhos in Greek meaning "flame-coloured") is an iron sulfide mineral with the formula Fe(1−x)S (x = 0 to 0.125). It is an iron-deficient nonstoichiometric variant of FeS, the mineral known as troilite. Pyrrhotite is also called magnetic pyrite, because the color is similar to pyrite and it is weakly magnetic. The magnetism decreases as the iron content increases, and troilite is non-magnetic. Pyrrhotite is generally tabular and brassy/bronze in color with a metallic luster. The mineral occurs with mafic igneous rocks like norites, and may form from pyrite during metamorp
Key facts
- Mineral.name
- Pyrrhotite
- Mineral.image
- Pyrrhotite-Sphalerite-Quartz-195225.jpg
- Mineral.imagesize
- 260px
- Mineral.caption
- Brassy, tabular crystals of pyrrhotite, with sphalerite and quartz, from Nikolaevskiy Mine, Primorskiy Kray, Russia. Specimen size: 5.3 × 4.1 × 3.8 cm
- Mineral.formula
- Fe1−xS (x = 0 to 0.125)
- Mineral.IMAsymbol
- Pyh
- Mineral.strunz
- 2.CC.10
- Mineral.system
- Monoclinic, with hexagonal polytypes
- Mineral.class
- Prismatic (2/m) (same H-M symbol)
- Mineral.symmetry
- A2/a
- Mineral.unit cell
- a = 11.88 Å, b = 6.87 Å, c = 22.79 Å; β = 90.47°; Z = 26
- Mineral.color
- Bronze, dark brown
- Mineral.habit
- Tabular or prismatic in hexagonal prisms; massive to granular
- Mineral.cleavage
- Absent
- Mineral.fracture
- Uneven
- Mineral.mohs
- 3.5 – 4.5
- Mineral.luster
- Metallic
- Mineral.refractive
- Opaque
via Wikipedia infobox
Wikidata facts
- Subclass of
- intermediate good
- Has part
- iron
- Named after
- fire
- Image
- Muséum de Nantes - 023 - Pyrrhotite (Russie).jpg
Show 12 more facts
- described by source
- New International Encyclopedia
- chemical formula
- Fe₇S₈
- Commons category
- Pyrrhotite
- Nickel-Strunz 9th edition (updated 2009)
- 2.CC.10
- color
- brown
- streak color
- black
- Nickel-Strunz '10th ed', review of (9th ed/ 2009 update)
- 2.CC.10
- crystal system
- monoclinic crystal system
- Mohs' hardness
- 4
- IMA Mineral Symbol
- Pyh
- Strunz 8th edition (series ID, updated)
- II/B.09a
- 2022 Harmonized System Code
- 260400
via Wikidata · CC0
~12 min read
Encyclopedic overview
23 sectionsContents
- Structure
- Magnetic properties
- Identification
- Physical properties
- Optical properties
- Occurrence
- Formation
- Distribution
- United States
- Mining locations worldwide
- Canada
- US
- Australia
- Brazil
- Italy
- Kosovo
- Etymology and history
- Sulfide oxidation in construction aggregates leading to concrete degradation
- Uses
- Mineral abbreviations
- Synonyms
- References
- External links
Pyrrhotite (pyrrhos in Greek meaning "flame-coloured") is an iron sulfide mineral with the formula Fe(1−x)S (x = 0 to 0.125). It is an iron-deficient nonstoichiometric variant of FeS, the mineral known as troilite. Pyrrhotite is also called magnetic pyrite, because the color is similar to pyrite and it is weakly magnetic. The magnetism decreases as the iron content increases, and troilite is non-magnetic. Pyrrhotite is generally tabular and brassy/bronze in color with a metallic luster. The mineral occurs with mafic igneous rocks like norites, and may form from pyrite during metamorphic processes. Pyrrhotite is associated and mined with other sulfide minerals like pentlandite, pyrite, chalcopyrite, and magnetite, and has been found globally. thumb|Nickel arsenide#Crystal structure|NiAs structure of basic pyrrhotite-1C. thumb|Pyrrhotite with pentlandite (late Paleoproterozoic, 1.85 G… | Flickr thumb|Microscopic image of pyrrhotite under reflected light
==Structure== Pyrrhotite exists as a number of polytypes of hexagonal or monoclinic crystal symmetry; several polytypes often occur within the same specimen. Their structure is based on the NiAs unit cell. As such, Fe occupies an octahedral site and the sulfide centers occupy trigonal prismatic sites.
Excerpted from Wikipedia’s “pyrrhotite” article, available under the CC BY-SA 4.0 licence.