You are looking at a Fluorite skull.

Usually translucent and come in shades of white, brown, blue, yellow, purple, red, or colorless. Important balancer, healer. Opens heart (especially green), Throat Brow, Crown Chakra for clarity, overview, seeing additional truths/realities. Spleen bones, teeth, lungs, detoxification, anxiety, insomnia. Benefits the teeth and bones. People with arthritis, rheumatism, or spinal injuries have reported some relief from their conditions when they employ Fluorite in their healing regimen. Helps to rekindle sexual appetite and heighten intuitive powers. It is suggested using Fluorite in conjunction with Calcite and Pyrite. Assists in fighting mental disorder and gaining spiritual awakening. Helps one become more aware of the higher levels of reality and can anchor and free one from overstimulation on the psychic plane.