Classic blue Halite (Trimingham Coll.)

Item Description

From a classic German locality comes a dramatic and rare large cluster of rare blue halite crystals. This piece has shocking and rich "electric-blue" color within the otherwise translucent halite. The impresssive waxy luster cubes reach 4.7 cm on edge. This is rare older material from the Bob Trimingham Collection (acquired in 1970 during the Soviet era). Rarely on the market and highly unusual material. From the CalTech website http://minerals.caltech.edu: Blue halite is the result of exposure to natural radiation. Initially, if halite (common salt) is exposed to gamma radiation, it turns amber because of F-centers. They are mostly electrons trapped at sites of missing Cl- ions. In time the electrons migrate to Na+ ions and reduce it to Na metal. Atoms of Na metal, in turn, migrate to form colloidal sized aggregrates of sodium metal. They are the cause of the blue color. Value of such a rare and fine piece??