Mortar is, quite literally, the building block of society. It is the material used to bind construction materials together and fill the gaps between them. From building a brick wall to a building, you’ll need to know how to make some form of mortar to make a reasonably sturdy structure.
It has been used since ancient times by civilized people to build buildings and walls and more. If ancient people can make mortar, why can’t you?
In ancient times, the Babylonians used a mortar based of mud and clay. Just get some clay mud that is wet enough to be a thick paste. If it isn’t that malleable, add water. If it’s too thin, add more clay or dirt to thicken it up. This isn’t a very sturdy mortar and you can expect it not to last all that long, but it will do in a pinch and last long enough. The key benefit of clay mortar is that clay and dirt are more abundant than any other resource for making mortar.
The Ancient Egyptians made mortar from gypsum and sand. If you’ve ever worked with plaster of Paris (gypsum plaster), you’ll know that gypsum is makes a soft material, but when added with sand becomes a little more sturdy. To make gypsum mortar, mix gypsum powder with water to make a slurry and add sand until it forms a thick paste.
Limestone is a clear rock mineral that can also be found in hardware/home improvement stores, but it can also be found in rock quarries as well. To make the mortar, you will need to bake the limestone. It will expand and turn white. Even though you can make lime mortar without this step, it is very important to include it. The reason being that untreated lime mortar is susceptible to water and can collapse. Whereas, when treated in a kiln the lime becomes “hydraulic” and is much more resistant to the weather.
After you let it cool off, add water to it. The solid stones will collapse and hiss, this is normal. Stir it to make an opaque slurry. Add sand until it makes a thick paste.
This is the most abundant mortar in modern times. You can find quick set cement in any hardware or home improvement store near you. If you can’t find any (it’s likely someone else had this idea and looted it all after TEOTWAWKI. If you’re lucky enough to have cement on hand, mix according to the instructions on the bag.