Darkmail

Darkmail is a set of magical enchanted chain mail +3. This armor provides an armor class of 2 and the normal protection modifiers any set of chain mail offers. It offers also a bonus to fire resistance of 20% and it has a weight of 9 lbs. This item appears in Baldur's Gate II: Shadows of Amn. It can be gained at the Ruined Temple area at the end of the subquest of the murders in Umar Hills from the shade of Patrick.

In-game description
"Whether by design or through exposure to intense heat in battle, the chain links of this armor are coal black throughout. While legends usually speak of knights in shining armor facing great beasts, the fire resistant enchantment on this suit suggests equally great, if unheralded, battles with fire breathing creatures."