Captain rank insignia

In the original concept of rank insignia, I decided that gold skulls would be used to denote the leaders. While the Chapter was based on the Spartans, I had more conventional ranks in the Chapter. Rather than just having battle-brothers, Sergeants, Captains, etc., I reverted to the Rogue Trader and took from modern U.S. rank structure, having Lieutenants, First Sergeants (Vet Sgts in certain Command Squads), etc.

Lieutenants had gold skulls while Captains had crossed bones added. This guy was a Captain.