Formed when lava cools quickly due to contact with air or water, obsidian is a naturally occurring material. Since it does not demonstrate crystallinity (the structural order of a crystal), it is classified as a mineraloid rather than a mineral. Obsidians are typically black, with variations of browns, greens, or tans. The coloring is dependent upon the type of inclusions (material trapped inside a mineral). Obsidians are made up of around 70% silicon dioxide (a natural compound made up of oxygen and silicon, also commonly known as silica) and have a smooth, glass-like appearance.
During the Stone Age, cultures valued obsidian for its uses. It was used to create arrowheads, sharp blades, other weapons, and tools. It was even used as the first mirror! In more recent years, obsidian has been used for ornaments and beads, and it is still highly valued today.
In our artifacts, such as the Owl figurine’s eyes, we use obsidian to give contrast and depth. Obsidian is thought to block negative energy. It is great for decorative art pieces, as the dark contrast against the gloss and shine brings out the stone's beauty.
(Obsidian Facts: Geology of The World - www.worldatlas.com)