Verrocchio worked on his clay model of the Colleoni monument from 1479 to 1483 in competition with other great sculptors of the time. Since Da Vinci began working with Verrocchio in 1466, he played a great role in the creation of this clay model. Da Vinci studied the anatomy of horses, and thus created many detailed sketches for the Colleoni monument. In 1483, Verrocchio's clay model and plans for the statue were chosen as the winner of the competition for the Colleoni monument. Da Vinci's idea for the bronze saving casting process was said to have played a major role in the choosing of Verrocchio's clay model (Kulenovic and von Platten).