These striking cabochons are drops of midnight with silver stars at the heart! Black star stone is a calcium magnesium silicate type of mineral that shows a distinctive star-like pattern called asterism on the surface when light is incident on it. It is found in Thailand, Tanzania, and Sri Lanka. Black star diopside or “Black Star of India” has a four-pointed star, while black-star sapphire displays six- or twelve-pointed star. The star effect is created by needle-like inclusions in the stone. The stone is believed to provide emotional balance, trauma healing, and spiritual connection.