Valdornûst were one member of roughly five animals unique to the Black Mountains. Their name meant "frostbeard" in the dwarven language. The dwarven clan Torgrymst Valdornûst used the Valdornûst for several things and as a result it became their clan name.
Valdornûst were hardy, sure-footed, goat-like animals, similar in appearance to Mountain Goats but they were a third larger and had longer horns which curled down to their cheeks.
The dwarves used them to ride over the rough terrain of the mountains as well as utilizing them for the production of milk, wool and meat. They were much more useful than Horses or donkeys because they had exceptional balance and gave a very smooth ride. They would find a safe path in rough territory with great ease. Some dwarven clans rode them into battle.