Tetrataenite | |
---|---|
General | |
Category | Native element minerals |
Formula (repeating unit) | FeNi |
IMA symbol | Ttae[1] |
Strunz classification | 1.AE.10 |
Crystal system | Tetragonal |
Crystal class | Domatic (m) (same H-M symbol) |
Space group | Pm |
Unit cell | 22.92 ų |
Identification | |
Formula mass | 57.27 gm |
Color | gray white, silver white |
Crystal habit | Granular – Common texture observed in granite and other igneous rock |
Cleavage | none |
Fracture | malleable |
Mohs scale hardness | 3.5 |
Luster | metallic |
Streak | gray |
Diaphaneity | opaque |
Density | 8.275 |
Common impurities | Co, Cu, P |
References | [2][3][4] [2] |
Tetrataenite is a native metal alloy composed of chemically-ordered L10-type FeNi, recognized as a mineral in 1980.[5] The mineral is named after its tetragonal crystal structure and its relation to the iron-nickel alloy, taenite, which is chemically disordered (A1) phase with an underlying fcc lattice.[6] Tetrataenite is one of the mineral phases found in meteoric iron.[7][3][8] Before its discovery in meteoritic samples, experimental synthesis of the L10 phase was first reported in 1962 by Louis Néel and co-workers, following neutron irradiation of a chemically disordered FeNi sample under an applied magnetic field.[9][10][11] Compared to the magnetically soft, chemically disordered A1 phase (taenite), the tetragonal L10 structure of tetrataenite leads to good hard magnetic properties, including a large uniaxial magnetocrystalline anisotropy energy.[10][12] Consequently, it is under consideration for applications as a rare-earth-free permanent magnet.[13]
:12
was invoked but never defined (see the help page).:7
was invoked but never defined (see the help page).