Libras are intelligent and nice. Libras birthstones act as a charm or lucky stone and help them face challenges and give them strength of purpose. Agate is a talisman stone for Libras. Talismans are amulets or other pieces of jewelry believed to give its wearer magical powers. Libra talisman is engraved on agate, which is a banded variety of chalcedony. Agate is believed to increase intelligence in a way that the Libra birthstone enables its wearer to see the truth, and at the same time keep the person calm and focused by helping him accept the circumstances.
Here are some great agate pieces that can be found at Satin Doll & Co.

Agate and Jade bracelet

Battle Strong Agate and Glass Beaded Dangle earrings

Evergreen Green Agate necklace

Forever Green Agate and Glass bracelet

Horizon Agate earrings