Adamantine Dust

Adamantine Dust is the result of exposing any item made by the Drow to sunlight. Any Drow item turns into dust, whether it's worn at the moment or stored away in the Bag of Holding or the inventory. The only probable way to protect your items is by entering the surface when its dark and storing the item in a safe container. This item appears in Baldur's Gate II: Shadows of Amn and Baldur's Gate II: Enhanced Edition.

In-game description
"This is a pile of Adamantine dust, most likely the end result of exposing a Drow item to the light of day."