Ancient Roman architecture
Although concrete had been used on a minor scale in Mesopotamia, Roman architects perfected Roman concrete and used it in buildings where it could stand on its own and support a great deal of weight. The first use of concrete by the Romans was in the town of Cosa sometime after 273 BC. Ancient Roman concrete was a mixture of lime mortar, aggregate, pozzolana, water, and stones, and was stronger than previously-used concretes. The ancient builders placed these ingredients in wooden frames where they hardened and bonded to a facing of stones or (more frequently) bricks. The aggregates used were often much larger than in modern concrete, amounting to rubble.
Stone veneer
Thin stone veneer was first developed in the late 19th century, but there were materials developed much earlier that foreshadowed the use of stone veneer. Parts of the Roman Coliseum were made out of marble veneer that can no longer be seen. The holes in structure of the Coliseum are from the anchors of the veneer panels. Structures throughout the Roman Empire were made in part out of stone blocks, including the Segovia aqueduct in Spain, which was made out of granite blocks. People in the Roman Empire also developed concrete (out of cement and rubblestone), which helped builders expand structures greater than before. Stone was used as a part of the facings of these new concrete structures in the Roman Empire, as seen in the Coliseum.