3.7" Kidney Ore (Botryoidal Hematite) - Morocco

Hematite is a mineral form of iron oxides and major iron ore. It is harder but more brittle than pure iron, and colors can range from black to steel gray, brown, and red. Its botryoidal variety is commonly referred to as Kidney Ore.

Kidney ore's globular, bubbly shape is a result of layered growth around a nucleus, such as a speck of sand or dust. As more material is deposited, the spheres grow larger and eventually overlap with other nearby spheres. They all eventually fuse together to form the botryoidal cluster.