Tetrachromium Carbide, Cr₄C

In the preparation of chromium in the electric furnace, Moissan sometimes saw large metallic ingots covered with reddish-brown needles, often 1 to 2 cm. long, and of density 6.75. Similar glittering needles were also met with in the geodes which formed in the middle of the melt of chromium. Moissan attributed to them the formula Cr₄C, but this has not been confirmed.