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.^[1] There are three other known Fe-Ni meterotic minerals: kamacite, taenite, and tetrataenite. The pair of minerals antitaenite and taenite constitute the first example in nature of two minerals that have the same crystal structure (face centered cubic) and can have the same chemical composition (same proportions of Fe and Ni) - they differ in their electronic structures: taenite is a high magnetic moment alloy whereas antitaenite is a low magnetic moment alloy. This unique difference in electronic structure was first established in 1999^[2] and arrises from a high-magnetic-moment to low-magnetic-moment transition occurring in the Fe-Ni bi-metallic alloy series.^[3] The same electronic structure transition is believed to be a causal factor in Invar behaviour. Willamette Meteorite A meteorite is a natural object originating in outer space that survives an impact with the Earths surface without being destroyed. ... An alloy is a homogeneous mixture of two or more elements, at least one of which is a metal, and where the resulting material has metallic properties. ... Minerals are natural compounds formed through geological processes. ... General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ... General Name, Symbol, Number nickel, Ni, 28 Chemical series transition metals Group, Period, Block 10, 4, d Appearance lustrous, metallic and silvery with a gold tinge Standard atomic weight 58. ... Look up element in Wiktionary, the free dictionary. ... Enargite crystals In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. ... Worlds second largest Meteorite in Culiacan, Mexico A meteorite is a relatively small extra-terrestrial body that reaches the Earths surface. ... Chondrules in the chondrite Grassland. ... Kamacite is a mineral. ... Taenite is a mineral found naturally on Earth mostly in iron meteorites. ... Invar, also called FeNi36, is an alloy of iron (64%) and nickel (36%) with some carbon and chromium. ...

References

1. ^ D.G. Rancourt and R.B. Scorzelli. Low Spin γ-Fe-Ni (γLS) Proposed as a New Mineral in Fe-Ni-Bearing Meteorites: Epitaxial Intergrowth of γLS and Tetrataenite as Possible Equilibrium State at ~20-40 at % Ni. Journal of Magnetism and Magnetic Materials 150 (1995) 30-36
2. ^ D.G. Rancourt, K. Lagarec, A. Densmore, R.A. Dunlap, J.I. Goldstein, R.J. Reisener, and R.B. Scorzelli. Experimental Proof of the Distinct Electronic Structure of a New Meteoritic Fe-Ni Alloy Phase. Journal of Magnetism and Magnetic Materials 191 (1999) L255-L260
3. ^ K. Lagarec, D.G. Rancourt, S.K. Bose, B. Sanyal, and R.A. Dunlap. Observation of a composition-controlled high-moment/low-moment transition in the face centered cubic Fe-Ni system: Invar effect is an expansion, not a contraction. Journal of Magnetism and Magnetic Materials 236 (2001) 107-130.

• Mindat with location data
• Webmineral data