The one crop that never fails! Laid randomly or coursed, this style is the most common. Found in various sizes and colours, field flint is flint that has not been worked, either by hand or by water (see Cobbles). It is often graded before going into a wall. In rural and agricultural settings field flint is frequently used on domestic and agricultural structures. Miles of long field walls to retain livestock can still be seen in most of the Southern counties. Regularly laid by estate and farm workers field flint walls make good use of a free source of building material.