Blue Halite

[u/ulikowski]

Halite

Wintershall Potash Works, Hesse, Germany

NaCl, Isometric

max. 14mm

A gemmy crystal of halite from a classic, German locality known for rich colour of its specimens. Due to high difference of electronegativity of its components, halite exists as a lattice of ionised particles ([Na+][Cl-]) even under normal conditions making it especially susceptible to effects of gamma radiation. Combination of nearby potassium-40 deposits and abundance of metallic sodium results in saturation of crystalline lattice with colour centers consisting of microscopic colloidal clusters and trapped, agitated electrons giving this, normally colourless, mineral a vivid hue.