Chromium (Cr) Deposits

Important minerals :

• Chromite : FeCr₂O₄

Types of chromite deposits :-

• High grade ore with very low iron-oxide
  • Ex- Sukinda-Nausahi (Cr :Fe =3:1)
• Aluminous chromite with Fe₂O₃ more than 20% but less than 30%
  • Ex- Kondapalli (AP) (Cr :Fe =2:1)
• Ferriferous chromite with Fe₂O₃ more than 30%
  • Ex- Jojohatu (Bihar)
• Siliceous chromite with high SiO₂ content
  • Ex- Pauni (Maharashtra) (Cr :Fe =1.6 : 1)

• Banded or Stratiform type, as in Sukinda and Nausahi area.
• Lensoid, as in Kondapalli, Chaibasa, Pauni

Indian deposits :-

Stratiform or Layered Chromite	Associated with mafic/ ultramafic layered intrusions formed in calm environment (Precambrian)
Podiform chromite	Irregular geometry, found in disturbed environment, Phanerozoic in age
Sukinda ultramafic complex, Orissa	Stratified beds inclosed in a sequence of Dunite-peridotite
Sithampundi chromite, Tamilnadu	Stratiform deposit in anorthosite
Byrapur chromite, Karnataka	Podiform deposit