Eldvergar

The most mysterious of all dwarf races, the Eldvergar or Magma Dwarves are attested only in ancient legend. They are said to dwell deep in the world's core, where the heat of volcanoes is formed. Such tales speak of their dark, black skin, glowing red eyes, and fiery orange hair and beards – which some say are quite literally formed of fire. These rumors may contain little or no truth, but every now and then a magically-forged item appears in the hands of some wandering adventurer that bears the strange runes of the magma dwarves, and which nothing but the hottest of flames – usable only by the eldergar due to their immunity to heat – can alter.