The Mineral hematite
Hematite is one of the most common minerals. The color of most red and brown rock, such as sandstone, is caused by small amounts of Hematite. It is also be responsible for the red color of many minerals. Non-crystalline forms of Hematite may be transformations of the mineral Limonite that lost water, possibly due to heat.
Color
Black, gray to silver gray, brown to reddish brown, red. Some specimens are iridescent, and other are multicolored or banded gray and dark red.
Properties
Streak
Red to reddish brown |
Hardness
5 - 6 |
Transparency
Opaque |
Specific Gravity
4.9 - 5.3 |
Luster
Metallic to dull |
Cleavage
None, but occasionally exhibits rhombohedral and basal parting. |
Fracture
Uneven |
Tenacity
Brittle |
Other ID Marks
Hematite is paramagnetic, meaning it is slightly attracted to magnetic fields.
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Crystal Habits
Crystals occurs in thin plates, as well as bundles of small micaceous plates, and in thin splinters. Most commonly massive, mammilary, botryoidal, reniform, oolitic, stalactitic, and radiating. Scalenohedral and rhombohedral crystals occur, as well as tabular and groups of tabular crystals. Crystals are often striated. Dendritic and rosette forms are also found. May form as a pseudomorph after other minerals, especially as octahedral crystals of Magnetite.
Varieties
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Dark green to greenish blue variety of Chalcedony speckled with red or brown spots. (May also refer to Hematite with red or brown spots.) For additional information, see the gemstone page on Bloodstone.
Uses
Hematite is the principle ore of iron. Huge quantities are mined throughout the world for industrial production. It is the source for roughly 90 percent of all iron mined in the United States. Hematite was largely used in the past as a red and brown pigment, although nowadays cheaper sources have been substituted. Well formed Hematite crystals are popular among mineral collectors, and tumbled, highly lustrous Hematite from Brazil makes a very popular, inexpensive specimen for amateur collectors.
Hematite is also used as a minor gemstone. It is cut and polished into cabochons for jewelry and ornaments, fashioned into beads for bracelets and necklaces, and carved into ornamental figures.
Noteworthy Localities
Hematite has numerous good localities, and therefore only the finest will be mentioned. Large and thick crystals have been found in Minas Gerais, Brazil, particularly at Antonio Pereira, Congonhas de Campo, Jaguaracu, and Itabira. Lustrous plates with flat or tabular crystals come from Novo Horizonte and Brumado, Bahia, Brazil. Most of the tumbled, polished Hematite comes from Minas Gerais.
Cumberland, in Cumbria, England, is a major source of Hematite specimens, especially the Specularite variety, as well as much of the globular and stalactitic specimens. Another classic occurrence is Rio Marina, on the island of Elba, Italy. The Cavradi Gorge in Tujetsch, Grischun, Switzerland is well-known for its outstanding and unique lustrous tabular Hematite crystals.
Morocco has also been a recent producer of fine collectible Hematite, with special note on Nador in the Nador Province, where excellent crystals and clusters have been found. The Wessels Mine in Hotazel, in the Kalahari manganese fields of South Africa has produced outstanding lustrous crystals including the rare prismatic forms.
In the U.S., enormous Hematite deposits exists throughout the western area of Lake Superior, especially in the Menominee iron range, Iron Co., Michigan. "Iron Roses" occur in the Thomas Range in Utah, as well as in numerous localities in Arizona, namely Aztec Peak, Gila Co.; Bouse, Yuma Co.; and in the Buckskin Mountains in La Paz Co. A classic New York locality is Chub Lake, St. Lawrence Co.
Distingushing Similar Minerals
Quite a few minerals may resemble Hematite in appearance, but Hematite's red streak is a distinguishing property. Lepidocrocite, which has a red streak like Hematite, is softer (4.5 - 5), and is translucent in thin splinters, and Goethite is less lustrous.