Pyrite sun
Variety FeS2
Also called Pyrite dollar and Pyrite disc
Take care.
- Breaks down in damp air: Keep it dry and in steady humidity; some crumble or rot as they take on moisture.
About it
Flat, radiating discs of pyrite grown between layers of shale above coal seams near Sparta, Illinois. Often sold polished; keep them dry, as they can decay in damp air.
- Type
- Variety
- Group
- Pyrite variety
- Formula
- FeS2
- Hardness (Mohs)
- 6–6.5
- Specific gravity
- 4.9–5.2
- Streak
- greenish black
- Lustre
- metallic
- Crystal system
- Isometric (cubic)
- Colours
- brassy yellow, bronze
- Transparency
- opaque
- Cleavage and fracture
- none; radiating structure, uneven fracture
Typical values: real specimens vary. For more, see mindat.org.