akaganeite
Sign in to saveAlso known as akaganéite, IMA1962-004
Akaganeite, also written as the deprecated Akaganéite, is a chloride-containing iron(III) oxide-hydroxide mineral, formed by the weathering of pyrrhotite (Fe1−xS), an iron-deficient sulfide.
Key facts
- Mineral.name
- Akaganeite
- Mineral.image
- Earth-and-Man--Akaganeite.jpg
- Mineral.caption
- A piece of the mineral akaganeite. Exhibit of the "Earth and Man" Museum in Sofia, Bulgaria. Discovered in Kaskasnyunchorr, Khibiny Massif, Kola Peninsula, Russia
- Mineral.category
- Oxide mineral
- Mineral.formula
- Fe3+O(OH,Cl)
- Mineral.IMAsymbol
- Akg
- Mineral.strunz
- 4.DK.05
- Mineral.system
- Monoclinic
- Mineral.class
- Prismatic (2/m) (same H-M symbol)
- Mineral.symmetry
- I2/m
- Mineral.unit cell
- a = 10.561, b = 3.031 c = 10.483 [Å]; β = 90.63°; Z = 1
- Mineral.color
- Yellowish brown, rusty brown
- Mineral.luster
- Earthy
- Mineral.streak
- Brownish yellow
- Mineral.diaphaneity
- Transparent, translucent
- Mineral.gravity
- 3.52
via Wikipedia infobox
~2 min read
Encyclopedic overview
4 sectionsContents
- Occurrence
- See also
- References
- External links
Akaganeite, also written as the deprecated Akaganéite, is a chloride-containing iron(III) oxide-hydroxide mineral, formed by the weathering of pyrrhotite (Fe1−xS), an iron-deficient sulfide.
Akaganeite is often described as the β phase of anhydrous ferric oxyhydroxide , but some chloride (or fluoride) anions are commonly included in the structure, so a more accurate formula is . This formula derives from the more general expression , where x = 1/6 ≃ 0.167. As the anion is doubly negatively charged, to maintain the electroneutrality in the crystal lattice, the electrical charge deficit (2x) in must be compensated by two monovalent anions, one and one . Nickel may substitute for iron, yielding the more general formula
Excerpted from Wikipedia’s “akaganeite” article, available under the CC BY-SA 4.0 licence.