Lime-based mortars are construction materials made primarily from lime, water, and aggregates like sand. They have been used for centuries in building and masonry due to their flexibility, breathability, and ability to accommodate movement in structures. Lime mortars cure through a process called carbonation, where they absorb carbon dioxide from the air, allowing them to harden over time. These mortars are often preferred for restoring historic buildings because they are compatible with traditional materials and help prevent damage to older masonry. Unlike modern cement mortars, lime-based mortars are less rigid, which helps to protect structures from cracking and other forms of deterioration.