Coloured scanning electron micrograph (SEM) of the surface of a freshly erupted tooth. The indentations once contained ameloblast cells that secreted the enamel onto the developing tooth. The crown (visible part) of the tooth is covered in enamel. It is the hardest substance in the human body. The picture was created as part of a cooperation with Quintessenz Publishing. Magnification: x600 when printed at 15cm wide.