Naquite
Natural iron monosilicide (FeSi) — first found in the 1960s at Donetsk and initially rejected under the name fersilicite.
Intro adapted from Wikipedia (CC BY-SA).
Naquite is an IMA-recognized mineral species in the native element class, with the chemical formula FeSi.
It crystallizes in the cubic crystal system (space group P2_13). It is a member of the Brownleeite structural group.
Key properties: Mohs hardness 6.5; specific gravity 6.186; Grayish black streak; Metallic luster.
IMA symbol Naq, IMA status: approved, named in 2010.
Found in the heavy mineral fraction of a podiform chromitite deposit in the peridotite of an ophiolitic harzburgite. Likely the product of a strongly reducing environment and possibly are xenocrysts derived from a mantle source.
It is found associated with Luobusaite.
The name refers to Naqu (Nagchu) Prefecture, Tibet, near the locality that produced the first samples.