Английская Википедия:Cliftonite
Шаблон:Infobox mineral Cliftonite is a natural form of graphite that occurs as small octahedral inclusions in iron-containing meteorites. It typically accompanies kamacite, and more rarely schreibersite, cohenite or plessite.[1]
Cliftonite was first considered to be a new form of carbon, then a pseudomorph of graphite after diamond, and finally reassigned to a pseudomorph of graphite after kamacite.[2] Cliftonite is typically observed in minerals that experienced high pressures. It can also be synthesized by annealing an Fe-Ni-C alloy at ambient pressure for several hundred hours. The annealing is carried out in two stages: first a mixture of cohenite and kamacite is formed in air at ca. 950 °C; it is then partly converted to cliftonite in vacuum at ca. 550 °C.[3]
The Campo del Cielo region of Argentina is noted for a crater field containing a group of distinctive iron meteorites.
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