Gold vs Pyrite
| Property | Gold | Pyrite |
|---|---|---|
| Fórmula | Au | FeS2 |
| Sistema Cristalino | Cubic (Isometric) | Cubic (Isometric) |
| Classe Mineral | 01 Native Elements | 02 Sulfides and Sulfosalts |
| Dureza Mohs | 2.5-3.0 | 6.0-6.5 |
| Cor | Golden yellow | Pale brass-yellow |
| Brilho | Metallic | Metallic |
| Traço | Golden yellow | Greenish-black to brownish-black |
| Transparência | Opaque | Opaque |
| Clivagem | None | Indistinct |
| Fratura | Hackly | Conchoidal to uneven |
Key Differences
- ◆ Pyrite (fool's gold) has a greenish-black streak; gold has a golden-yellow streak — the definitive field test.
- ◆ Gold has a much higher specific gravity (up to 19.3) versus pyrite (4.95–5.10).
- ◆ Pyrite is harder (6–6.5) than gold (2.5–3); gold is easily scratched with a knife.
- ◆ Pyrite forms distinctive cubic or pyritohedral crystals; gold occurs as irregular nuggets, flakes, and dendrites.
- ◆ Pyrite is brittle and breaks into fragments; gold is extremely malleable and ductile.