From a regular "Diamond" formation (can be established by having the centers of a two-faced line arm turn 3/4): Each dancer will move ahead to assume the position and facing direction of the dancer ahead in the diamond. Finishes in a diamond. NOTE: It is important to understand that a diamond has "centers" and "points." The centers are generally understood to be those who have hands or arms joined (as a result of a previous movement performed) while the points are the one who don't. Regular diamonds have all facing the same way while "facing" diamonds have alternate dancers facing opposite.
Dewey Berry 1972
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.