Stone is an abundant material found in all planets and rings(?). It is guaranteed to spawn on every planet, alongside copper and iron deposits. It is a decently important material, as it is currently the placeholder to make templates.
Stone is found in mountains, that also contain many other materials, such as Silicon, Sulfur, Flint, Oil, Ruby, Ice, and Helium.
In-game description
A resource found in nearly all planets. It is not recommended to use for structures but is often used in crafting simple objects.