Greenstone Ring

Greenstone Ring is an item of jewelry which can be sold to stores. It is common treasure frequently dropped by enemies. This item appears in Baldur's Gate, Baldur's Gate: Enhanced Edition and Baldur's Gate II: Shadows of Amn, and Baldur’s Gate II: Enhanced Edition.

In-game description
"A ring is a small band of precious metal that is used as jewelry. Some rare rings have had enchantments placed upon them that confer various magical abilities. These rings are highly sought after, especially by those of the adventuring profession."