While plunge is the amount by which a line element departs from horizontality, usually therefore measured in a vertical plane containing the line element or linear feature, pitch or rake is that a line elemet makes with the strike of the plane in which it is contained and measured in this plane. A pitch is always acute angle unless the line element is oriented in the direction of true dip of the containing plane. As an example, hornblende grains in an amphibolite may form a distinct lineation in a plane which is a plane of schistosity. The angle that the linear hornblende crystals make with the strike of the schist within the plane of schistosity is Rake or Pitch. But the plunge of the lineation of these hornblende crystals will be measured in a vertical plane containing the dominant trend of hornblende grains.