Occurs in Pinal County.
Chemical Formula: CaFe3+2(Si2O7)O(OH)
Specific Gravity: 3.9-4.1
Luster: Vitreous to submetallic
Hardness: 5.5-6
Ilvaite is a calcium iron silicate mineral that often forms as black, prismatic crystals or columnar masses. It is found in metamorphic and hydrothermal environments.
Next Pinal County mineral: Iodargyrite