Schreibersite
An iron-nickel phosphide mineral found in iron meteorites, often as bright plates or needles in the metal.
Schreibersite is a phosphide, a mineral of iron and nickel combined with phosphorus, with the formula (Fe,Ni)₃P. It is almost unknown in ordinary Earth rocks but common in iron meteorites, stony-irons and some chondrites. It forms large plates and rims around troilite nodules, and as thin needles called rhabdites scattered through kamacite. It is named after Carl von Schreibers, a director of the natural history collections in Vienna in the early 19th century.
Schreibersite interests chemists studying the origin of life. When it corrodes in water it releases reactive forms of phosphorus, an element essential for DNA and cell membranes, and some researchers have proposed that meteorites delivered phosphorus in a useful form to the early Earth. In metallography, the distribution of schreibersite also helps reveal how metal cooled. It is abundant in IAB irons such as Canyon Diablo and in Sikhote-Alin, where large crystals are visible in sliced pieces.
On an etched face, schreibersite stands out as bright, hard, tin-white to pale bronze plates or veinlets that resist the acid. It is magnetic but more brittle than the metal around it and can make sawing difficult.
Related terms
Level: Enthusiast Teens and adults