Antitaenite

Antitaenite is a meteoritic metal alloy mineral composed of iron and nickel, 20–40% Ni (and traces of other elements) that has a face centered cubic crystal structure. Antitaenite is a meteoritic metal alloy mineral composed of iron and nickel, 20–40% Ni (and traces of other elements) that has a face centered cubic crystal structure. Its existence as a new mineral species occurring in both iron meteorites and in chondrites was first recognized in 1995 but the IMA didn't approve paramagnetic antitaenite (a variety of taenite now). Gamma (fcc) Fe-Ni alloys with low-Ni (c. 25% Ni) are probably inhomogeneous on a nanometer scale. There are three other known Fe-Ni meteoritic minerals: kamacite, taenite, and tetrataenite.