In the article Delamination on polygonal masonry blocks in Peru, an oddity was shown on the surface of polygonal masonry blocks - rock delamination like a shell. A version with an explanation in the article is also suggested.
It turns out that this is not the only place with a similar phenomenon. Similar delamination is found on granite blocks in ancient buildings in Egypt:
As you can see, the rock flakes off parallel to the surface. If this is the direction of the layers, then it would be visible when laying the block - it would be laid differently, horizontally to the layers. Natural granite does not have such distinct layers. There are interlayers, foreign inclusions in it, but the layers do not peel off.
Strange "bald spots" on a granite statue in Egypt.
The official explanation is surface stresses in granite. But where do they get it? This is not masonry.
Promotional video:
Delamination on a number of blocks in masonry. The photo is also interesting in that the blocks go over another wall, they are L-shaped. This can be achieved if the vertical layer on the blocks has been removed by several centimeters. Either it is casting or block forming. Explainable, except for one thing - how to repeat the rock or imitation of the composition like natural granite?
Or maybe this is natural granite, but masonry was molded from it at a time when it was a plastic mass squeezed out of the bowels, geo-concrete. Let me remind you for new readers that according to my version, granite is not an igneous rock, but cold fluidolites. Previously wrote about the approximate physics of the process here.
Photo from this location:
Not the only example, here's another:
As he wrote in an article about delamination in blocks of polygonal masonry, the explanation is this: a layer of plastic rock mixed with the clay formwork and changed its properties, then peeled off. Or, with the slow expansion of the masses that had not yet hardened inside, the part of the outer layers that had already gained hardness peeled off.
No one can clearly comment on these examples of formwork marks on blocks:
Formwork marks are visible on the lower blocks.
Perhaps there were shields, and the masses were simply molded into them.
Here the rock was raked, cutting off layer by layer, as we do with a spoon over butter or ice cream. Or when in a cafe a ball of ice cream is scooped up from a container with a special spoon.