What is painting technique of Birth of Venus by Sandro Botticelli?

Botticelli's Venus was the first large-scale canvas created in Renaissance Florence. He prepared his own tempera pigments with very little fat and covered them with a layer of pure egg white in a process unusual for his time. His painting resembles a fresco in its freshness and brightness. It is preserved exceptionally well and the painting today remains firm and elastic with very little cracks. For more info, view the related link below.