Cinnabar vs Pyrite
| Property | Cinnabar | Pyrite |
|---|---|---|
| Formula | HgS | FeS2 |
| Crystal System | Trigonal | Cubic (Isometric) |
| Mineral Class | 02 Sulfides and Sulfosalts | 02 Sulfides and Sulfosalts |
| Mohs Hardness | 2.0-2.5 | 6.0-6.5 |
| Color | Scarlet red, brownish-red | Pale brass-yellow |
| Luster | Adamantine | Metallic |
| Streak | Scarlet | Greenish-black to brownish-black |
| Transparency | Translucent | Opaque |
| Cleavage | Perfect prismatic {1010} | Indistinct |
| Fracture | Conchoidal to uneven | Conchoidal to uneven |
Key Differences
- ◆ Cinnabar (HgS) is the mercury ore; pyrite (FeS2) is the most common sulfide — different metals entirely.
- ◆ Cinnabar has a vivid scarlet streak; pyrite has a greenish-black to brownish-black streak.
- ◆ Cinnabar (specific gravity 8.1–8.2) is far denser than pyrite (4.95–5.10).
- ◆ Cinnabar forms near volcanic hot springs; pyrite occurs in virtually all rock types.
- ◆ Cinnabar has trigonal crystal structure; pyrite is cubic.