Tscarborough - I am currently designing for a new build and have been looking for info on dipping bricks into lime wash before build. Is this what your talking about re mexican style bricks?We do it 3 or 4 times a year, sometimes for face brick, sometimes for thin brick. We use 1/1 white portland/type S lime and adjust the water to the amount of wash they want. Note that we are doing it to bricks, not a wall. An example would be a bag of white portland, a bag of lime and about 20 gallons of water. The slurry is kept stirred and the brick are then dipped, dried, and in the case of thin brick, sawn. That would give about 80% coverage of the brick. The only brick we do it to are Mexican handmade woodmolds as they are porous enough to absorb and hold the slurry.
For a typical hardfired face brick in the wall, you would use a thicker slurry and brush it on. Using a straight lime-wash will not last past the first rain unless you use a hydraulic lime.
That was an exaggeration, Dom, but for permanent lime wash it needs some portland. "Lime run" is usually just partially lime, it includes other salts that make it hard to remove.
I will post some pics from work tomorrow.
Table salt is not one of the normal salts coming out in brick, but it is still a salt and thus soluble and subject to migration. I do not think it would have any advantageous properties, only the opposite.