Helm of Brilliance

Helm of Brilliance is a helmet which offers protection from critical hits and its adds a 40% resistance to fire when equipped. This helmet also allows the wearer to use three spells as an ability once per day while equipped. These spells are: Fireball, Prismatic Ray and Sunray. This item appears in Baldur's Gate II: Shadows of Amn and this item will probably appear in Baldur's Gate II: Enhanced Edition.

It's sold by Ribauld in the Adventurer's Mart in his special stock which becomes available in Baldur's Gate II Chapter 6.

In-game description
"This helm is made of polished steel and set with diamonds, rubies and fire opals. The gems glow with an internal light, the source of which can only be magical. The helm makes the wearer resistant to fire as well as giving the wearer some spell abilities. These include fireball, prismatic spray and the sunray."