A neodymium borosilicate, Mg2Nd13(BO3)(8)(SiO4)(4)(OH)(3) (MgNdBSi-1), was obtained from a high-temperature (1400 degrees C), solid-state reaction under high-pressure conditions (4.5 GPa). MgNdBSi-1 contains six different types of Nd3+ coordination environments with three different ligands: BO3, SiO4, and OH groups. Mg2+ cations are only bond to BO3 groups and form porous two-dimensional layers based on 12-membered ring fragments. Surprisingly, the OH groups are retained at high temperature and reside at the center of Mg-BO3 rings.