When would you use a bolster chisel?

A bolster chisel and a lump hammer is used to cut out a section of brickwork. This could be to make an opening in an existing wall for adding a new window or door. Many professionals, when brick laying, will cut a brick in two by using the edge of their trowel, though a bolster chisel could be used instead.

Further to this being a wide bladed chisel trades use this for "knocking off" which is removing mortar and render in readiness for re-render etc