You are looking at a Kambaba Jasper skull pendant.

Also known as Brecciated Army Jasper, Camo Stone Kambaba Jasper is an exotic looking jasper from Africa, Its pattern includes speckles and concentric rings. It contains a jumbled jungle of forest green, mint green, black and brown. It is said to mystically soothe the nerves and state of mind. As with other jaspers, traditional lore says that it is good for grounding and protection. It is purported to be beneficial for plant growth and health, particularly in arid environments or where the soil is poor. Crystal healing lore says that Kambaba Jasper helps dietary stabilization, assimilation of vitamins and minerals, and cleansing the body of toxins.