Pentlandite - Occurrence, Properties, and Distribution

Introduction

Pentlandite, nickel iron sulphide, is the principal ore for nickel. Pentlandite is found in the form of massive granular aggregates. It appears as a brassy, gold-colored mineral, having similarities in characteristics to other sulfide minerals like pyrrhotite and chalcopyrite. Pentlandite may sometimes form isometric crystals, but occurrence as crystals is rare.

Pentlandite occurs in some mafic or ultramafic intrusive igneous rocks. It is formed during the cooling of a sulfide melt, which is in turn the result of a silicate melt.

Characteristics of Pentlandite

Some of the physical and structural characteristics of pentlandite are listed below:

• Color – Yellowish bronze
• Crystal Structure – Isometric
• Fracture – Conchoidal
• Hardness – 3.5-4 (Mohs scale)
• Streak and Luster – Light bronze to greenish black/ metallic
• Specific Gravity – 4.6-5

Occurrences of Pentlandite

Pentlandite is predominantly found in the Sudbury Impact Structure in Ontario. Some of the other areas where this mineral is found are Bushveld igneous complex in South Africa, and Yilgarn crater in Australia.

References

• Pentlandite – Rruff Project, Arizona
• Pentlandite – Ohio State University
• Pentlandite Group - Mindat