When discussing the loss of Sten's sword with him, Sten says that the blade was forged specifically for his hand alone. However, the description of the sword says that it was recovered from the invasion of Thedas and granted to him upon receiving his mission.
Sten also mentions that the sword was forged from a rare material known as blue steel. Unlike Starfang, however, its material is simply referred to as generic steel rather than informally listed as a separate material type.
Asala, with Yusaris, are featured as the two swords standing point down in the Start Game menu screen. Yusaris being the leftmost sword and Asala being the other sword.
In spite of its importance, you can sell Asala almost immediately after completing the quest, an action which goes totally unnoticed by Sten.