A cluster of Arsenopyrite
crystals.
A close-up view.
CHEMISTRY - FeAsS
CRYSTALLOGRAPHY - Monoclinic (Pseudo-orthorhombic)
CRYSTAL GROWTH AND HABITS - Crystals are typically blocky or tabular with striations parallel the {001}. It can also be massive to granular.
COLOR AND OTHER OPTICAL PROPERTIES - Yellowish silver color on a fresh surface. Opaque
HARDNESS - 5.5 - 6
SPECIFIC GRAVITY - 6.0 - 6.2
LUSTER - Metallic
BREAKABILITY - Distinct cleavage on {101}; uneven fracture. Brittle
OCCURRENCE - Commonly one of the first minerals to form in hydrothermal deposits. Also found in gold, tin and high temperature quartz veins associated with pegmatites.
ASSOCIATED MINERALS -
MINERAL NAME - From its composition - arsenic and pyrite.