Usually, the objective piece is held clasped in the flintknapper's hand, with a durable piece of fabric or leather protecting the flintknapper's palm from the sharpness of the flakes removed. The tip of the flaking tool is placed against the edge of the stone tool and pressed hard, removing a small linear or lunate flake from the opposite side. The process also involves frequent preparation of the edge to form better platforms for pressing off flakes. This is usually accomplished with abraiders made from a coarse-grained stone such as basalt or quartzite. Great care must be taken during pressure flaking so that perverse fractures that break the entire tool do not occur. Occasionally, "outrepasse" breaks occur when the force propagates across and through the tool in such a way that the entire opposite margin is removed.