Crystal structure of kunzite. Artwork of several representations of the structure of the mineral kunzite: the cut and polished gemstone (top left); a natural, irregular specimen (lower left); atomic and crystal structure (right). Atoms (depicted as blue balls) form the regular, repeating crystalline structure that produces the larger columnar structures. The flat, external surfaces arise from cleavage planes where the lattice can be easily broken. Kunzite is the pink variety of spodumene, a monoclinic lithium aluminium silicate (formula: Li.Al.Si2.O6). It is a pleochroic gemstone, one that varies in colour intensity when viewed from different directions, as seen at upper left.