The Corona Nox ("Crown of Night") is an artefact of the Night Lords Traitor Legion that takes the form of a crown formerly worn by the Primarch Konrad Curze. It had a number of rubies known as bloodstones and a single diamond embedded within its surface that contrasted with its obsidian frame.
It first served as the sign of Curze's rule over his homeworld of Nostramo. Eventually it became the symbol of office for his rightful successor as the ruler of the Night Lords Legion after Curze's death.
The Corona Nox was an artefact fashioned in the form of a crown by the Night Haunter himself, forged from the adamantium recovered from the planetary crust where his gestation capsule had crashed into Nostramo when it emerged from the Immaterium.
Curze wore it all through his life, and when he might have screamed with the insanity and terror wrought by his haunting visions of the future, it calmed him. When he would have listened to the whispers of the Warp, it deafened him. When he burned with vengeance for the perceived injuries he felt that his father, the Emperor, wrought upon him, it sated his anger and stored it away.
This artefact would lead the First Captain on a ten-thousand-year-long odyssey to recover the artefact and claim his right as his Primarch's successor. But Sahaal would have to contend all along the way with other factions who sought to claim it, such as the Aeldari, the Imperium and his own Night Lords rivals.
- Lord of the Night (Novel) by Simon Spurrier