Hematite is a very common mineral, coloured black to steel or silver-gray, brown to reddish brown, or red. It is mined as the main ore of iron. Varieties include Bloodstone, Iron Rose, Kidney Ore, Martite, Paint Ore, Specularite (Specular Hematite), Rainbow Hematite and Titano-hematite. While the forms of hematite vary, they all have a rust-red streak. Hematite is harder than pure iron, but much more brittle. When shaped into ornaments, it is often called black diamond.
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Since polished hematite is considered by many to be a gemstone, it has been used in jewelry over the course of the last 50 years in North America, especially in the western United States. Hematite can be found used in jewelry and art created by the Native Americans. Also part of the hippie movement of the 1960s included the eclectic mix-match of differing styles of clothing and accessories, and hematite, due to its uniqueness, became popular.