Mineral phase
- IMA name
- Akaganeite
- IMA Code
- Akg
- Class
- non-silicate mineral
- Compound type
- oxide-hydroxide
- Comments
- formula given as Fe3+(O,OH,Cl) in Webmineral
- Formula
- (Fe3+,Ni2+)8(OH,O)16Cl1.25/bulletnH2O
- Chemical formula
- (Fe3+,Ni2+)8(OH,O)16Cl1.25 • nH2O
- Elemental formula
- (Fe3+)7-8 (Ni2+)0-1 (H)9-10 (O-)9-10 (O2-)6-7 (Cl-)1.2-1.3
- Isotope mixture type
- terrestrial abundance
- Composition comments
- Ni may possibly be > 1
- Oxides
-
Formula Fe2O3 NiO H2O Cl Mass fraction (%) 79.7 3.92 11.48 6.05
Strunz
- Class
- oxides - hydroxides - arsenites (04)
- Division
- metal:oxygen = 1:2 and similar (04.D)
- Family
- with large (+/- medium-sized) cations; tunnel structures (04.DK)
- Code
- 04.DK.05
Dana
- Major class
- oxides and hydroxides (III)
- Class
- hydroxides and oxides containing hydroxyl (06)
- Type
- where X+++O OH (06.01)
- Group
- -Akaganeite- group (06.01.06)
- Code
- 06.01.06.01
- Phase type
- crystalline
- Crystal system
- monoclinic
- Crystal class
- prismatic
- Crystal class symbol
- 2/m (C2h)
- Crystal spacegroup
- P2/m
- Comments
- Effective space group: I2/m
- Molar mass
- 761.37 g/mol
- Density
- 3.52 - 3.55 g/cm3
- State NTP
- solid
- Refringence type
- biaxial
- Refraction index nα
- 1.99 - 2.19 (calc.)
- Pure color
- brown
- Color
- brown, rusty brown
- Diaphaneity
- transparent to opaque