Axinite with a chemical formula CaMgAl3BO3SiO4O12(OH) is a complex boron silicate.
Most of the known Axinite minerals are of the Axinite-(Fe) type.
Axinite was named in 1787 after the Greek word axine, which means “ax”, in allusion to the sharp crystals of this mineral. The individual member types were originally Ferro-axinite, Magnesio-axinite, and Mangan-axinite.
Axinite forms in characteristic, flattened tabular crystals with sharp edges. It crystallizes in the triclinic System. Also grainy, bladed, columnar, in platy aggregates, in rosettes of sharp crystals, and massive. Crystals are often striated or have parallel line growths. It is generally lilac brown but can also be colorless, brown, violet, and blue. It is transparent to nearly opaque, with hardness 6 – 7 on the Mohs scale; the luster is vitreous.