Oxides and Hydroxides: Hematite (haematite)

Composition: Fe₂O₃

Crystal system: Trigonal; variety of habits including well crystallized aggregates, massive, botryoidal, pisolitic and earthy forms

4.7.1
crystalline hematite
Iron Monarch SA Australia

Properties:

• Metallic to submetallic lustre
• Variable color; crystalline and specular forms steel-grey, massive and earthy forms dull red
• Red to red-brown streak
• Knife barely scratches crystalline types (Mohs Hardness 5-6); earthy forms appear quite soft
• High density
• No cleavage
• Uneven fracture
• Not ferromagnetic
• Soluble in concentrated hydrochloric acid (HCl)
  

Occurrence:

Hematite is one of the most common oxide minerals. It occurs as an accessory mineral in igneous and metamorphic rocks, with other oxides in iron-bearing sedimentary rocks, with sulfides in some hydrothermal ore deposits and as a weathering product of iron-bearing minerals .

4.7.2 crystalline hematite Iron Monarch SA Australia	4.7.3 reniform hematite Cumberland England

4.7.4 reniform hematite Cumberland England	4.7.5 reniform hematite Cumberland England

4.7.6 reniform hematite Cumberland England	4.7.7 crystalline hematite Iron Monarch SA Australia

Hematite is the most important source of iron.