pozzolana
pot-suh-LAH-nuh
Definition
A specific type of volcanic ash from the Bay of Naples region, traditionally used as a primary ingredient in Roman concrete to give it hydraulic and self-healing properties.
Etymology
Derived from the Italian town Pozzuoli, near Mount Vesuvius, where this volcanic earth was first extensively mined for use in building materials by the Romans.
In the news
The article identifies pozzolana as the essential volcanic ash ingredient in the Roman concrete recipe that allows for the long-term chemical growth of minerals like tobermorite.
Roman concrete piers built two thousand years ago along the Mediterranean coast are stronger now than the day they were poured, because seawater seeping into the volcanic ash mix triggers the slow growth of a rare crystal called aluminous tobermorite tha
Read the full article ↗ScienceBlog.com