Taenite

Taenite (Fe,Ni) is a mineral found naturally on Earth mostly in iron meteorites. It is an alloy of iron and nickel, with nickel proportions of 20% up to 65%.

Taenite
Widmanstatten patterns 2.jpg
Widmanstätten patterns of Kamacite and Taenite, from a meteorite currently in the Natural History Museum, London.
General
CategoryMetals and intermetallic alloys
Formula
(repeating unit)
γ-(Ni,Fe)
Strunz classification1.AE.10
Crystal systemIsometric
Crystal classHexoctahedral (m3m)
H-M symbol: (4/m 3 2/m)
Space groupFm3m
Identification
Colormetallic grayish to white
CleavageNone
FractureHackly fracture
TenacityMalleable, flexible
Mohs scale hardness5-5.5
Lustermetallic
Streaklight gray
DiaphaneityOpaque
Specific gravity7.8–8.22
Other characteristicsmagnetic, not radioactive
References[1][2]
Widmanstätten pattern showing the two forms of Nickel-Iron, Kamacite and Taenite, in an octahedrite meteorite

The name is derived from the Greek ταινία for "band, ribbon". Taenite is a major constituent of iron meteorites. In octahedrites it is found in bands interleaving with kamacite forming Widmanstätten patterns, whereas in ataxites it is the dominant constituent. In octahedrites a fine intermixture with kamacite can occur, which is called plessite.

Taenite is one of four known Fe-Ni meteorite minerals: The others are kamacitetetrataenite, and antitaenite.

PropertiesEdit

It is opaque with a metallic grayish to white color. The structure is isometric-hexoctahedral. Its density is around 8 g/cm3 and hardness is 5 to 5.5 on the Mohs scale. Taenite is magnetic, in contrast to antitaenite. The crystal lattice has the c≈a= 3.582±0.002 Å.[3] The Strunz classification is I/A.08-20, while the Dana classification is 1.1.11.2 . It is hexoctahedral (cubic) in structure.

Meteorite localities with taeniteEdit

  • Campo del Cielo crater in Argentina.
  • Henbury Meteorites Conservation Reserve in Australia.
  • Canyon Diablo in Arizona.

This article uses material from the Wikipedia article
 Metasyntactic variable, which is released under the 
Creative Commons
Attribution-ShareAlike 3.0 Unported License
.