What is 'Pozzolana'?

Pozzolana refers to a natural volcanic ash that has the unique property of hardening when mixed with lime and water, creating a strong and durable material similar to cement. This material was crucial in Roman architecture, as it allowed for the production of concrete that could be used for a variety of structural applications. The Romans utilized pozzolana extensively in the construction of their famous pavilions, public buildings, and infrastructure projects, such as aqueducts and roads, which contributed to their innovative and enduring architectural legacy.

The choice about Roman pottery pertains to ceramics and does not relate to pozzolana's function in construction. The reference to a type of stone used in sculpture focuses on more traditional carving materials, while the mention of marble relates to a specific type of metamorphic rock prized for its aesthetics rather than its use as a building material like pozzolana. Each of these alternatives denotes materials with distinct applications that do not capture the essential qualities and historical significance of pozzolana in architecture.