Lense strand, Kyanite (blue) AA, 15 x 08mm

Blue Kyanite is also called cyanite or kyanite. The name Kyanite is derived from the Greek "this sthénos" (twofold strength, twofold power). This describes a very unusual property of Kyanite: depending on the direction in the crystal, it has two very different hardnesses (so-called hardness anisotropy). Spellings such as distin, disthin or distene have not become established in the retail and wholesale trade.