Jade Ring

Increases the Agility of the Hero by 1 when worn.

One of the items created by the high elf Veth'talia during her career as a fighting spellcaster was this ring made of the purest jade. The item appears to have been carved directly from a single chunk of this precious stone and is a circle as perfect as any seen on Azeroth. When worn, the owner's eyes change color to a deep, rich, almost glittering green.

Source
Tyrande can find one in The Awakening of Stormrage, chapter 3 of the Warcraft III night elf campaign, Eternity's End.

Maiev can find one in Rise of the Naga, chapter 1 of the Frozen Throne sentinels campaign, Terror of the Tides.