This piece is a Blue Andean Opal from Peru. Opal consists of silicon, hydrogen and oxygen.
Opal is "the stone of happy dreams and changes". It helps you understand your potentials and aspire to live them fully. Andean Opal instills a knowledge of "right action".
On the physical level it is good for the heart, the lungs and thymus.
On the psychological level Andean Blue Opal activates the heart chakra while providing grounding and centering. It is a joyful and uplifting stone, freeing oneself of depression, and allowing one to be calm and centered. It helps letting go of negative emotional energies.