Arcanum: Of Steamworks and Magick Obscura
Black Mountain Clan is in the northernmost region of the Stone Wall Mountains.
It's the clan Bates was obsessed with. Stennar shared the steam engine technology with him, betraying dwarven tradition to not share technology with humans, bringing down judgement from the Wheel Clan and Loghaire upon them. They are now exiled to the Isle of Despair.
Gudmund Ore Bender finds the punishment too harsh, so he stayed behind to record and share history of that day.
(Gudmund Ore Bender)
They actually have never been on the Isle of Despair. Only a single member of the Wheel Clan has been exiled there and for completely unrelated reasons.
A delegation of elves, sent from the Silver Lady herself, came not long after Bates built his first steam engine. Technology spread fast and the elves were hit first and hardest. If the Black Mountain clan was not punished, there would be an Elven-Dwarven war. The Wheel Clan already decided punishment, but the elves refused. They claimed rights as the afflicted and as judges and wanted exile. They wanted to be the vessel of that retribution. Threatening war is out of character for elves, though. Loghaire feared war as cataclysmic for Arcanum, so he sacrificed the Black Mountain clan's honor, against his responsibility. He should have brought the matter to the dwarves or allowed war, so now he has exiled himself. His story is over, but he gives the Living One a letter from the elven delegation that mentions M'in Gorad. He suggests you find Qintarra. Maybe Stillwater has hints to its location.
(Loghaire Thunder Stone)