Arsenopyrite

Real mineral · common · FeAsS

Iron arsenic sulfide and the most common arsenic mineral. Forms in high-temperature hydrothermal veins and metamorphic rocks. Often associated with gold deposits. Produces a garlic odour when struck due to arsenic vapour release.

Identity

Formula

FeAsS

Chemical class

sulfide

Also known as

Mispickel, Arsenical pyrite

Crystallography

Crystal system

monoclinic

Habits

prismatic, massive, granular

Fracture

uneven

Physical properties

Mohs hardness

5.5

Density

6.07 g/cm³

Luster

metallic

Colors

silver-white, steel gray

Streak

black

Transparency

opaque

Geology

Origins

hydrothermal, metamorphic

Host rocks

granite, schist, quartz veins

Associated minerals

Pyrite, Gold, Chalcopyrite, Sphalerite

Geography

worldwide

Classification

Rarity

common

Gem quality

No

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