The niobium hemicarbide (Nb 2 C) has at least three known polymorphs: α (Pnma or Pbcn), β (P 3 ¯ 1 m ) , and γ (P6 3 /mmc) as a function of temperature. Identification of these phases has been notoriously difficult particularly for the lower-temperature variations (α and β) because of their long-range vacancy ordering. In the current study, an overall Nb 2 C composition has been processed by hot isostatically pressing NbC and Nb powders together which did not fully homogenize. Using neutron diffraction and selected area electron diffraction, the C6 (P 3 ¯ m 1 ) structure was identified in the Nb 2 C. The formation pathway for this phase is postulated from the high density of stacking faults observed in the NbC.