In stone masonry, ashlar is quarried stone used for building. In the symbolism of Freemasonry, the “rough” and the “perfect” ashlar are two of the three ‘movable jewels’ of the Mason’s Lodge. Together, they represent man in his potential and realized state, respectively.
The rough ashlar is analogous to the alchemical idea of base matter, through which purified alchemical salt is obtained by dissolution: both the pure salt and the perfect ashlar symbolize the human soul realized through spiritual and intellectual pursuits.
The Masonic concept may be related to an ancient belief that the stonecutter’s art brought order to the world by harnessing the chaos inherent within it.