Rainbow obsidian spheres

Rainbow obsidian is a type of natural glass that gets its name from the iridescent sheen that appears on its surface when it is cut and polished. This iridescence is caused by the presence of tiny inclusions of magnetite, which refract light in different directions.
The rarity of rainbow obsidian stems from the specific conditions required for its formation. As the lava cools rapidly, the mineral inclusions need to align perfectly to create the rainbow effect. This intricate process occurs only in limited geological environments, making rainbow obsidian a rare find indeed.