Provenite

About Hematite

Fe₂O₃

The most important ore of iron and one of the most widespread iron oxides, hematite forms steel-gray, mirror-bright crystals and plates as well as red earthy and botryoidal masses. Its cherry-red streak separates it from similar dark minerals.

Show 4 localities on the map

Photos of Hematite

Double-terminated ribbed hematite 'fan' from the Montreal Mine, Wisconsin.
Hematite · Montreal Mine (Gogebic Range)
Double-terminated ribbed hematite 'fan' from the Montreal Mine, Wisconsin.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Hematite specimen from Rio Marina, Elba, Italy (NMNH 79088-02).
Hematite · Rio Marina
Hematite specimen from Rio Marina, Elba, Italy (NMNH 79088-02).
Photo: Smithsonian NMNH, Department of Mineral Sciences · CC0 · Source

Where Hematite is found (4)

Brazil

Italy

United Kingdom

United States

Hematite on the same specimen with other minerals

Same specimen Hematite with Quartz at Diamond Willow Mine (Pearl Station)

2 specimen photo(s) from this locality show quartz with hematite together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Same specimen Hematite with Quartz at Göschenen Valley

1 specimen photo(s) from this locality show quartz with hematite together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Same specimen Hematite with Dolomite at Serra das Eguas (Brumado)

1 specimen photo(s) from this locality show dolomite with hematite together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Same specimen Hematite with Dolomite at Beckermet Mine (Egremont)

1 specimen photo(s) from this locality show dolomite with hematite together. The pairing comes from the photographer's file name and label, so the relationship between the two minerals is not specified.

Identity

Also called
haematite; specularite (specular hematite); kidney ore; iron rose
Group
Hematite group
Strunz
4.CB.05 · 4 Oxides and hydroxides
Name origin
From the Greek haima, 'blood', alluding to the red colour of powdered or earthy material.
Elements
Fe, O

Physical properties

Color
Steel-gray, sometimes with iridescent tarnish; dull to bright red
Streak
Cherry-red to reddish brown
Luster
Metallic luster
Transparency
Opaque
Mohs hardness
5–6
Density
5.255–5.26 g/cm³
Cleavage / fracture
No true cleavage; parting on {0001} and {10-11}; fracture uneven to subconchoidal; brittle
Magnetism / fluorescence
Only very weakly magnetic (weak ferromagnet/canted antiferromagnet) and not noticeably attracted by an ordinary magnet

Crystallography

Crystal system
Trigonal
Space group
R-3c
Structure
Corundum-type structure of Fe3+ and O; hexagonal cell a = 5.038, c = 13.772 (angstrom), Z = 6.
Typical habit
Rhombohedral, pseudocubic or prismatic crystals, thin tabular plates and rosettes ('iron roses'); also radiating fibrous, reniform and botryoidal ('kidney ore'), micaceous (specularite), earthy, oolitic and massive
Twinning
Penetration twins on {0001} or with {10-10} as composition plane; lamellar twinning on {10-11}
Optical data
Uniaxial (-); omega = 3.15-3.22, epsilon = 2.87-2.94; pleochroic (brownish red / yellowish red) in thin edges; strong internal reflections blood-red

Formation and use

Formation
Accessory in felsic igneous rocks, as sublimate in volcanic rocks, in high-temperature hydrothermal veins, in contact-metamorphic deposits and metamorphosed banded iron formations; also a common cement and constituent of sedimentary iron formations and an alteration product of other iron minerals. Associated with ilmenite, rutile and magnetite, and with goethite, siderite and lepidocrocite.
Uses
Principal iron ore; red, purple and brown iron-oxide pigments; beads, carvings and jewellery; radiation shielding and ballast.
Stability and care
Hard but brittle; protect bright metallic crystal faces from scratching and store specimens separately.

Related minerals

Related minerals
Magnetiteilmenitegoethite
Polymorphs
Maghemite
Can be confused with
Magnetitegoethiteilmenite

Sources

  1. SRC-229 · Book
    Handbook of Mineralogy - HematiteAnthony, J.W.; Bideaux, R.A.; Bladh, K.W.; Nichols, M.C. · 2005 · Mineralogical Society of America
  2. SRC-232 · Website
    HematiteWikipedia contributors · Wikipedia

Draft data from the Provenite workbook. Check entries against the cited sources before relying on them. Photos are open-licence images from Wikimedia Commons; the author and licence are given with each photo.