How to identify Pyrite

To correctly identify Pyrite (Iron Pyrite), check each of these features in order. Many rocks and minerals look alike, so cross-reference multiple properties before deciding.

Step-by-step identification

1. 1

   Color

   Overall color and any zoning or banding

   Pale brass-yellow to golden-yellow, often tarnishing to a darker, duller brassy color.

2. 2

   Luster

   How the surface reflects light: metallic, vitreous, dull

   Distinctive metallic luster, often bright and reflective.

3. 3

   Texture

   Grain size and surface feel: coarse, fine, glassy

   Typically forms well-defined crystals, often cubic, octahedral, or pyritohedral. Can also be massive, granular, or radiating.

4. 4

   Crystal Form

   Shape of visible crystals or crystal faces

   Cubic, octahedral, or pyritohedral crystals are common, often with striations on cube faces. Also found as massive, granular, or radiating aggregates.

5. 5

   Cleavage

   How it breaks: flat cleavage planes vs irregular fracture

   Poor to indistinct cleavage on {011}. Typically fractures conchoidally or unevenly.

6. 6

   Geological Environment

   The rock formation and setting where it occurs

   Found in igneous, metamorphic, and sedimentary rocks. Common in hydrothermal veins, magmatic sulfide deposits, contact metamorphic zones, black shales, coal seams, and as a detrital mineral in sediments.

Key Facts

Hardness

6-6.5 (Mohs scale)

Specific Gravity

4.95-5.10 g/cm³

Crystal System

Isometric

Color

Pale brass-yellow to golden-yellow

Luster

Metallic

Transparency

Opaque

Fracture

Conchoidal to uneven

Cleavage

Poor to indistinct on {011}

Composition

Iron sulfide (FeS₂)

Physical characteristics

• Crystal Habit: Cubic, octahedral, pyritohedral, massive, granular, radiating
• Cleavage Type: Poor/Indistinct
• Fracture Type: Conchoidal to uneven
• Tenacity: Brittle
• Luster Type: Metallic

Explore Pyrite