Lost Ashes of War is a Key in Elden Ring.
Empty ashes of war, devoid of any memories of battle.
Unable to apply any kind of affinity in their current state, but can be used by Smithing Master Hewg of the Roundtable Hold to recreate other ashes.
Thus does the copy pass into becoming the genuine article.
Elden Ring in-game description
Lost Ashes of War Location

Additional Insights Into Lost Ashes of War
- Effect: Used to duplicate Ashes of War
- Rarity: Common
- Sell Value: 500 Runes
- Lost Ashes of War can be traded.
- On-Hand Capacity: 99
- Storage Capacity: 600