
mineral
Arsenopyrite
Arsenopyrite (FeAsS)
AI-generated identification · may be incorrectHardness: 5.5-6.0; Color: Silver-white to steel-gray; Luster: Metallic; Crystal Structure: Monoclinic; Cleavage: Distinct; Specific Gravity: 6.07; Streak: Black.
- Hardness
- 5
- Color
- Silver-white to steel-gray
- Luster
- Metallic
Identified More mineral →
Explore Arsenopyrite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5.5-6.0; Color: Silver-white to steel-gray; Luster: Metallic; Crystal Structure: Monoclinic; Cleavage: Distinct; Specific Gravity: 6.07; Streak: Black.
Formation & geological history
Formed in high-temperature hydrothermal veins, pegmatites, and contact metamorphic deposits. It is often found associated with gold, quartz, and other sulfides.
Uses & applications
Primary ore of arsenic; historically used to produce arsenic trioxide for pesticides and pigments. Occasionally collected as specimens or for its gold content in associated deposits.
Geological facts
When struck with a hammer, arsenopyrite emits a strong garlic-like odor due to the release of arsenic vapors. It is known as 'mispickel' in older geological literature.
Field identification & locations
Identify in the field by its metallic silver-gray color, high density, and garlic smell when crushed. Common in mining districts such as Cornwall (UK), Germany, and Ontario (Canada).