A bend initiation creates a lip on the flake where the platform edge is wrenched away from the core edge.  The lip is usually excurvate in plan view, extending the width of the platform, and often curves outward slightly in profile, towards the flake’s ventral surface.  Since a bend-initiated flake lacks a Hertzian cone, the platform will lack a ring crack or umbo, and an eraillure will not be present on the flake’s ventral surface.  It is important not to confuse an umbo with a platform lip.