: Beren Valthôl

From what I can remember of the LOTR itself, we have insufficient data on which to speculate.

The only thing I can think of is the differences in which a spear and a sword are wielded. A spear is mainly a thrusting weapon whereas a sword can also be a slashing one. Perhaps the spear was greatly damaged by penetrating Sauron's body whereas only a relatively minor portion of Narsil was damaged.

Perhaps Telchar was a greater smith than the forger of Aeglos.