Xifengite ( Fe₅ Si₃) is a rare metallic iron

silicide A silicide is a type of chemical compound that combines silicon and a (usually) more electropositive element. Silicon is more electropositive than carbon. Silicides are structurally closer to borides than to carbides. Similar to borides and carb ...

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...

. The

crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macro ...

system of xifengite is

hexagonal In geometry, a hexagon (from Greek , , meaning "six", and , , meaning "corner, angle") is a six-sided polygon. The total of the internal angles of any simple (non-self-intersecting) hexagon is 720°. Regular hexagon A '' regular hexagon'' has ...

. It has a specific gravity of 6.45 and a

Mohs hardness The Mohs scale of mineral hardness () is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material. The scale was introduced in 1812 by t ...

of 5.5. It occurs as steel gray inclusions within other meteorite derived nickel iron mineral phases. It was first described in 1984 and named for the eastern passageway, Xifengkou, of the

Great Wall of China The Great Wall of China (, literally "ten thousand ''li'' wall") is a series of fortifications that were built across the historical northern borders of ancient Chinese states and Imperial China as protection against various nomadic gro ...

. The type locality is the Yanshan meteorite of the Hebei Province, China. It has also been reported from dredgings along the

East Pacific Rise The East Pacific Rise is a mid-ocean rise (termed an oceanic rise and not a mid-ocean ridge due to its higher rate of spreading that results in less elevation increase and more regular terrain), a divergent tectonic plate boundary located alon ...

. The other known natural iron silicide minerals are gupeiite (), hapkeite (), linzhiite (), luobusaite (), naquite (), suessite (), and zangboite ().Mindat, http://www.mindat.org

References

Iron(II,III) minerals Meteorite minerals Hexagonal minerals Minerals in space group 193 Minerals described in 1984 {{mineral-stub

See also

References