Obsidian is a mineral-like rock formed as a result of rapidly cooled lava. Pure obsidian is dark in appearance, though the colour varies depending on the presence of impurities. Iron and other transition elements may give the obsidian a dark brown to black colour.
Black obsidian contains the most potent energies, such as the elements of fire, water, and earth. Obsidian also acts as a protective stone guarding a person against negativity.
Learn more about Obsidian in our blog What on Earth is Obsidian?