日本鉱物科学会年会

The trapiche emerald have two domains having different symmetry in arm area. CL images show the presence of bright and dark bands running parallel to the growth direction in the arm. The dark band contains more Na and Mg content than the bright band. Under the SEM, the {10-10} surfaces of the arm show innumerable irregularity form and the dark bands in CL correspond to the recess. The results indicated that the arm area is formed by the cell growth of two domains from the core surface.