Rubble-work

Rubble masonry is rough, unhewn building stone set in mortar, but not laid in regular courses. It may appear as the outer surface of a wall or may fill the core of a wall which is faced with unit masonry such as brick or cut stone.

The wall at Grave Circle A, Helladic cemetery of Mycenae, Greece, 16th century BCE

Rubble masonry core of the unfinished Alai Minar in the Qutb complex, India, c. 1316 CE

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