Three emeralds
Two natural uncut emeralds and a Gilson synthetic cut stone. Like ruby and red spinel, emerald is coloured by chromium. Emerald contains beryllium as an integral part of its crystalline structure (Be_3 Al_2 (SiO_3)_6). Beryllium is a uniquely interesting element since, during the evolution of the universe from the Big Bang, it was not produced by nuclear reactions in stars and supernova explosions like most of the other chemical elements but by the interaction of cosmic rays with interstellar gas between the stars.
Three emeralds
Two natural uncut emeralds and a Gilson synthetic cut stone. Like ruby and red spinel, emerald is coloured by chromium. Emerald contains beryllium as an integral part of its crystalline structure (Be_3 Al_2 (SiO_3)_6). Beryllium is a uniquely interesting element since, during the evolution of the universe from the Big Bang, it was not produced by nuclear reactions in stars and supernova explosions like most of the other chemical elements but by the interaction of cosmic rays with interstellar gas between the stars.