Kyanite 1 Piece Raw Minerals Stones Rocks Collecting (7)

Kyanite 1 Piece 499 gr - cm 12 x 6 x 3.2 Raw Minerals Stones Rocks for Collection, cut base, it stands, only a piece, as in photo.
Variety of Aluminum Silicate.

Kyanite is a mineral, chemically classifiable as an Aluminum subnesosilicate, with the chemical formula Al2SiO5. The name derives from the Greek kyanos which means blue, referring to the typical color of the crystals.
Therefore it does not contain cyanide, as one might mistakenly be led to believe!
Kyanite constitutes together with andalusite and sillimanite the three polymorphic forms of Al2SiO5 of which kyanite is the high pressure member. The presence of these polymorphic forms is extensively used to characterize metamorphic rocks.