Here's an article I found a while back. I wasn't able to verify the authenticity of it.
Aqeeq, in english, is also known as:
Cornelian
Carnelian
Red Agate
Agate
Chalcedony
Red Chalcedony
And here are some hadith on its merits:
A Hadith from Janabe Salman Farsi states that the last Prophet requested Imam Ali to wear a ring on the right so that he may be listed among the Muqarrabeen (those near to Allah). The Imam asked the Prophet as to who the Muqarrabeen were, to which the Prophet replied Janabe Jibreel and Janabe Mikaiel.
Then the Imam inquired as to which stone should he wear. The Prophet replied Aqiq (cornelian), as this red stone had accepted the Oneness of Allah, the Prophethood of the last Prophet, and the vicegerency of Ali ibne Abi Talib, and the heavens for Ali's friends and Shias.
The 8th Imam was once asked why the 1st Imam wore his ring on the right hand. The Imam replies that Imam Ali is the leader of the Ashabe Yameen, and the Ashabe Yameen are those records of actions will be given on the right hand. And secondly, the last Prophet also wore his rings on his right hand.
The Shias will identified by these symbols, having the ring on the right hand, praying 5 times a day at the right timings, giving charity, distributing among his religious brothers his belongings, ordering good actions and keeping people away from evil.
The 9th Imam stated that Aqiq takes away the poverty and dissolves differences in one's heart.
The 6th Imam stated that Aqiq brings safety while traveling.
The Prophet stated that Allah finds it difficult not to listen to the prayers of those who have Aqiq and Firoza rings on their fingers, and feels hurt to negate their prayers.
The 6th Imam stated on Durre Najaf, that all the Momineen and Mominaat feel happy when they sight this stone, and the pain of their eyes is relived. The Imam stated that he wants every Momin to have five rings. Yakoot ring is the best. The second is Aqiq as it is a stone which has affection for Allah and Ahle Bayt. Third is Firoza which gives strength to the eyes, expands the breast and strengthens the heart. Whenever a Momin goes for some work with a Firoza ring on his finger, his work is done. Fourthly one should wear the ring of Hadeed Cheeni but not always. Only when one is afraid of some mischief then he should visit that environment with this ring on at the stone keeps the devil away.
And the fifth ring should be that of Durre Najaf which
is found only in Najaf. When a person wears a ring of Durre Najaf, at his every glance towards it, Allah gives him the reward of Ziyarat, Hajj and Umrah, which are kept in his record of action. The reward is equal to the rewards of the Prophets and pious; if Allah had not been merciful towards the Shia, then every gem of Durre Najaf would have been costly but Allah made it readily available so that both rich and poor can wear it.
Also Imam al-Sadiq <a> has narrated: