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Hematite is a widespread mineral occuring in scattered grains through many of the igneous rocks. It is one of nature's most abundant pigments, giving the red color to sandstones such as those in the Grand Canyon. Large masses of specular ore are associated with metamorphic rocks. Oolitic hematite is found in extensive beds of sedementary origin. The chief deposits in the United States, which supply a high percentage of the world's iron ore, are grouped around the northwestern and southern shores of Lake Superior in Minnesota, Wisconsin, and Michigan. Part of it comes from the famous Clinton iron ore, a layer a foot or more in thickness; starting in New York State, and extending all down the Appalachian Mountains to Alabama, where it is ten or more feet thick and the basis of the birmingham iron industries. Then there are tremendous deposits of earthy to compact hematite, probably derived from limonite, around the west end of Lake Superior. This latter region yeilds around 75% of the iron for the U.S.. Loose earthy masses of hematite are often known as "ochre red." and were used by the Indians for war paint. Today the same sort of material is obtained by powdering hematite and using it for red paint. The red color in great stretches of rock is due to the presence of small amounts of hematite, acting as a cementing material. The red of the ruby, garnet, spinel, and the pink of feldspars and calcite are due to traces of hematite. This material is very common and found in every state. The most beautiful crystals have come from the island of Elba, and from Switzerland.
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