Random rubble walling
Random Rubble Walling, also called rubblework, is the use of undressed, rough stone, generally in the construction of walls. Dry-stone random rubble walls, for which rough stones are piled up without mortar, is the most basic form. An intermediate method is polygonal rubble walling, for which stones are split faced and roughly dressed to suit a specific pattern or design.
Galleted Random Rubble Walling features stones of varying sizes and joint widths with small fillets or gallets bedded into the mortar between the stones.
Random Rubble stonework bound with mortar was often used historically as an infilling between dressed wall faces as an inner ‘hearting’ or core to the external wall faces.
Many medieval cathedrals, ecclesiastical and historic properties were built in this manner.