Masonry Aggregate Crushed stone, gravel, or sand added to cement to make concrete. Ashlar Cut, squared building stone finely dressed on all sides adjacent to other stones. Requires only very thin mortar joints.
Random ashlar uses rectangular stones in discontinuous courses.
Coursed ashlar uses rectangular stones of the same height in each horizontal course, but each course may vary in height. Broken rangework arranges ashlar units into horizontal courses of varying heights, which may be divided into horizontal groups at various intervals. A horizontal course in a masonry wall which is of different color, texture, or size. Concrete An artifical, stonelike building material made by combining cement with aggregate and adding sufficient water to cause it to set and bind the materials together. There are various mixtures to meet specific performance requirements.