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.

The Mix
Lime mortars were the norm for centuries, and the secret of the perfect mix for any given situation was passed from father to son and from craftsman to apprentice over generations; the techniques also varied considerably across the country to suit the nature and performance of predominantly locally-sourced materials. There were few textbooks and no formal training. It was a matter of tradition and instinct supplemented by generations of experiment and sound experience.
This chain of knowledge was severely interrupted by the First World War and the near-universal adoption thereafter of stronger, faster-setting and consistent (but not always appropriate) cement-based mortars. To a large extent, today’s craftsmen have had to rebuild that knowledge base from scratch. But what if we have placed too much trust, and not enough understanding, in surviving texts, rather than analyzing the sound evidence of centuries-mortar— http://www.buildingconservation.com/articles/mythmix/mythmix.htm
Is there anything freer than chalk?
Where does one get one’s Cement?
That Cement is Brotherly Love and Affection comes from “Heart Work.” This is a major focus of the operative . With its focus upon Values, Morality, Divestment and Investment, Masonic Cement is slowly but surely created by the Masons so doing this Work.
But isn’t Cement just “Symbolic?” Speculative Speaking
Masons might assume that all this Masonic Cement talk is just Symbolic. They might assume that a literal translation would ever readily present itself should Masons try to find it within some Ritual. And should such Masons ever assume that Masonic Cement is just Symbolic, they would be very wrong.
Investigating the compounds necessary to bring about Cement requires exploration into the many types of Cements commonly used over the years. There are multitudes of mixtures that have been used in the past with the most widely spread formula being those used in Ordinary Portland Cement. The basic compounds that produce OPC come from limestone, alumina, silica and ferric sources. When properly prepared and appropriately mixed together with water, it creates a viscous fluid that readily hardens into solids with the utmost of Integrity.
Interestingly enough, the compounds required to create Cement are mentioned within Lectures throughout the World. Moreover, it is amazing to this Mason that it is a rare operative mason who knows this, especially since the Cement of Brotherly Love and Affection is such an overly emphasized articulation echoed throughout Masonic Work.
Let’s explore the making of Cement and see if you might guess where the “ingredients” are hidden within Operative Ritual.

One step toward making Cement is to take Limestone and remove Carbon Dioxide from it. This is usually done by breaking the material up and subjecting it to an intense heat source. At temperatures of 900 degrees centigrade, lime is created. Removal occurs more quickly at 1000 degrees though. Higher temperatures are counterproductive since something called, “dead-burn” lime is created which is nonreactive for Cement production purposes.

Coincidentally, charcoal burns at 1100 degrees centigrade. With this temperature being achieved, it can easily be used to raise the temperature of limestone to the necessary tipping point where it gives up its carbon dioxide. Doing so creates a compound called “Lime” or Calcium Oxide. This compound is used to create Lime Mortar, Roman Cement(1) and OPC.
For those of you who might not make the connection, Limestone is common Chalk.
Chalk, Charcoal, and Clay Chalk by Anthonyhttp://masonry.life