Wiktionary
n. A soft form of mortar made from sand and slaked lime.
Wikipedia
Lime mortar is a type of mortar composed of lime and an aggregate such as sand, mixed with water. It is one of the oldest known types of mortar, dating back to the 4th century BC and widely used in Ancient Rome and Greece, when it largely replaced the clay and gypsum mortars common to Ancient Egyptian construction.
With the introduction of ordinary portland cement (OPC) during the 19th century the use of lime mortar in new constructions gradually declined, largely due to portland's ease of use, quick setting, and high compressive strength. However the soft, porous properties of lime mortar provide certain advantages when working with softer building materials such as natural stone and terracotta. For this reason, while OPC continues to be commonly used in brick and concrete construction, in the repair and restoration of brick and stone-built structures originally built using lime mortar, the use of OPC has largely been discredited.
Despite its enduring utility over many centuries, lime mortar's effectiveness as a building material has not been well understood; time-honoured practices were based on tradition, folklore and trade knowledge, vindicated by the vast number of old buildings that remain standing. Only during the last few decades has empirical testing provided a scientific understanding of its remarkable durability.
Usage examples of "lime mortar".
Tharasamund and Princess Jorith half-lifted Padway up the stairs and propped him against a pile of sacks of lime mortar.
A layer of fist-sized stones in lime mortar, a layer of sand, another of mortar with smaller rocks, then a layer of mortar and gravel, and then the paving blocks .
Wooden tables with benches and chairs, floor of smooth lime mortar, brick walls—.
At the left side, a thin trail of smoke rose from the chimney of flint nodules set in brilliantly white lime mortar.
His thighs and upper body were free to move, but other than that, it was as if he had been cast in lime mortar.