In nine cases out of ten, the stone mastabas are but outwardly regular in construction.

The core is of roughly quarried rubble, mixed with rubbish and limestone fragments hastily bedded in layers of mud, or piled up without any kind of mortar.

The brick mastabas are nearly always of homogeneous construction.

The facing bricks are carefully mortared, and the joints inside are filled up with sand.

That the mastaba should be canonically oriented, the four faces set to the four cardinal points, and the longer axis laid from north and south, was indispensable; but, practically, the masons took no special care about finding the true north, and the orientation of these structures is seldom exact.