Researchers found that quicklime is the ingredient in Roman concrete that makes it last.
“‘[A]s soon as tiny cracks start to form within the concrete, they [lime clasts] can preferentially travel through the high-surface-area lime clasts. This material can then react with water, creating a calcium-saturated solution, which can recrystallize as calcium carbonate and quickly fill the crack, or react with pozzolanic materials to further strengthen the composite material.’ Here we have a convincing explanation of the reactions that, in ancient Roman concrete, ‘automatically heal the cracks before they spread.’”
The process is called self-healing. https://www.openculture.com/2023/01/the-mystery-finally-solved-why-has-roman-concrete-been-so-durable.html
Medieval tacticians used quicklime at sea to blind opponents before boarding their ships.
In the Roman Church, we could use this product for healing cracks or blinding opponents or both.