Yarlongite occurs in ophiolitic chromitite at the Luobusha mine （29°5′N 92°5′E, about 200 km ESE of Lhasa）, Qusum County, Shannan Prefecture, Tibet Autonomous Region, People＇s Republic of China. Associated minerals are： diamond, moissanite, wiistite, iridium （＂osmiridium＂）, osmium （＂iridosmine＂）, periclase, chromite, native iron, native nickel, native chromium, forsterite, Cr-rich diopside, intermetallic compounds Ni-Fe-Cr, Ni-Cr, Cr-C, etc. Yarlongite and its associated minerals were handpicked from a large heavy mineral sample of chromitite. The metallic carbides associated with yarlongite are cohenite, tongbaite, khamrabaevite and qusongite （IMA2007-034）. Yarlongite occurs as irregular grains, with a size between 0.02 and 0.06 mm, steel-grey colour, H Mohs： 5^1/2-6. Tenacity： brittle. Cleavage： （0 0 1） perfect. Fracture： conchoidal. Chemical formula： （Cr4Fe4Ni）29C4, or （Cr,Fe,Ni）29C4, Crystal system： Hexagonal, Space Group： P63/mc, a = 18.839（2） A, c = 4.4960 （9） A, V = 745.7（2） A^3, Z = 6, Density （calc.） = 7.19 g/cm3 （with simplified formula）. Yariongite has been approved as a new mineral by the CNMNC （IMA2007-035）. Holotype material is deposited at the Geological Museum of China （No. Ml1650）.
SHI NichengBAI WenjiLI GuowuXIONG MingFANG QingsongYANG JingsuiMA ZheshengRONG He
