Sarooj waterproof mortar

Another thread about an ancient Persian cooling technology for the hot/cold desert, called a Yakhchal or ice pit, made a reference to how these sometimes enormous buildings were built. The Wikipedia article on the yakhchal said

The yakhchāl is built of a unique water resistant mortar called sarooj, composed of sand, clay, egg whites, lime, goat hair, and ash in specific proportions, that is resistant to heat transfer and is thought to be completely water impenetrable

That caught my attention. Completely impenetrable? Dayum! I eventually found this video on how to make it (in Turkish with English subtitles):



Has anyone ever made this or something very similar? How did it perform if so? And if not, anyone want to try and tell us about it?

I have a project in mind to build a natural swimming pool in a place on a slope, so it will need reinforced, lined sides. Is this the inside lining of the pool? Or would something else be more practical?