Hematite

Hematite
Chemical composition	Fe2O3
Crystal system	Trigonal
Habit	Tabular to thick crystals; micaceous or platy, commonly in rosettes; radiating fibrous, reniform, botryoidal or stalactitic masses, columnar; earthy, granular, oolitic
Cleavage	None, may show partings on {0001} and {1011}
Fracture	Uneven to sub-conchoidal
Hardness	5.5–6.5
Refractive index	nω = 3.150–3.220, nε = 2.870–2.940
Specific gravity	5.26
Lustre	Metallic