Eagle-stone - Etite, a variety of argillaceous oxyd of iron, occurring in masses varying from the size of a walnut to that of a man's head. Their form is spherical, oval or nearly reniform, or sometimes like a parallelopiped with rounded edges and angles. They have a rough surface, and are essentially composed of concentric layers. These nodules often embrace at the centre a kernel or nucleus, sometimes movable, and always differing from the exterior in colour, density and fracture. To these hollow nodules the ancients gave the name of eagle-stones, from an opinion that the eagle transported them to her nest to facilitate the laying of her eggs.