Roaldite

Roaldite is a rare meteorite mineral containing iron, nickel and nitrogen ((Fe,Ni)₄N).

Roaldite
General
Category	Mineral
Formula (repeating unit)	(Fe,Ni)4N
Strunz classification	1.BC.05
Dana classification	1.1.18.2
Crystal system	Cubic
Crystal class	Hextetrahedral (43m) H–M Symbol: (4 3m)
Space group	P43m (no. 215)
Unit cell	a = 3.79 Å; Z = 1
Identification
Colour	Tin-white
Crystal habit	Platelets in kamacite
Mohs scale hardness	5.5-6.5
Lustre	Metallic
Diaphaneity	Opaque
Specific gravity	7.21
Optical properties	Isotropic
References	[1][2]

It was first described in 1981 for an occurrence in the Youngedin meteorite, Avon, Western Australia. It was named after Roald Norbach Nielsen (born 1928), a Danish expert in electron microprobe. The mineral has also been reported from the Jerslev meteorite, Sjaelland, Denmark, and the Canyon Diablo meteorite of Meteor Crater in Arizona. 

This article uses material from the Wikipedia article  Metasyntactic variable, which is released under the  Creative Commons Attribution-ShareAlike 3.0 Unported License.