The Iron Halo is a revered part of the Armoury of the Chapters of the Adeptus Astartes and is also a common Astartes award for valour. The Iron Halo is a halo-shaped ring that is positioned above the head of the wielder, usually mounted on the backpack of Space Marine Power Armour but sometimes mounted in the gorget. The Iron Halo is a prestigious honour that is granted only to the most exceptional of the Astartes within a Space Marine Chapter as a reward for uncommon initiative and valour. It is most often worn by the Chapter's Captains and Chapter Master, though Veteran Astartes and Sergeants can also earn the right to add it to their armour in certain circumstances. The Iron Halo appears to share the same basic technological mechanisms as the Space Marine Chaplain's Rosarius, as they both produce a protective effect using gravitic and now poorly-understood Conversion Field technology.
The Iron Halo emits a very strong gravitic Conversion Field around its wearer, which makes his armour even harder to pierce with enemy weapons. In addition it also provides its wearer with immense resilience to even the most potent weapons on the battlefield such as Lascannons and missiles of all varieties. The shield stands a good chance of deflecting many deadly projectiles that would slay a Space Marine without an Iron Halo with ease.
Notable Wearers of the Iron Halo
- Marneus Calgar - Chapter Master of the Ultramarines
- Pedro Kantor - Chapter Master of the Crimson Fists
- Cervan Dante - Lord Commander of the Blood Angels
- Cato Sicarius - Captain of the Ultramarines' 2nd Company
- Davian Thule - Captain and Force Commander of the Blood Ravens
- Titus - Captain of the Ultramarines' 2nd Company
- Codex: Blood Angels (4th Edition)
- Codex: Space Marines (4th Edition)
- Deathwatch: Rites of Battle (RPG), pp. 206-211
- Insignium Astartes
- Warhammer 40,000: Wargear (4th Edition)
- Warhammer 40,000: Space Marine (Video Game)