Location: The stones

Opals

Methaphysical Properties: Increase mental capacities such as creative imagination and other unused powers of the mind. Associated with the assimilation of protein, Pineal Gland function, Insulin regulation, the testicles, Parkinson's disease and memory.

There are many different color variations of opals:
Clear, white or water opals have been used as gazing tools as a way to look inward, a spiritual mirror. Opals are also helpful for enhancing dreamwork or assisting spiritual journeys.
Blue opals can help open up the third eye, sooth the throat chakra, and nm telepathic communications.
Fire opals (ranging from orange to red) can be used to stimulate change, manifest your ideas. They have also been associated with improving circulation.
Green opals help give an energy boost. Pink opals address emotional issues, offering nourishment and support to the heart chakra.

Corresponding Astrological Signs: Libra and Scorpion. It is the birthstone for the month of October.