Nano-scale reaction processes at the interface between apatite and aqueous lead

► The interface between apatite and aqueous Pb was examined by TEM. ► Pyromorphite forms epitaxially on the tip of apatite crystal parallel to the a axis. ► Pseudomorphism takes place at the reaction front of Pb precipitation on apatite. ► Interface-driven mechanism is important in the Pb precipitation on apatite crystal.