No bulk GeSn crystal existed prior to this work. Near 10 GPa the two elements resemble each other both electronically and structurally. Synthesis experiments at 10 GPa and 1500 K followed by annealing at 770 K using Ge and Sn starting materials and ex-situ analysis using transmission electron microscopy, scanning electron microscopy, and X-ray diffraction document the recovery of a Ge0.9Sn0.1 solid solution (space group P4(3)2(1)2, a = 6.014 (1) angstrom, c = 7.057 (1) angstrom, Z = 12).