Calcium hydroxid: glue for stone blocks
Natural Calcium oxid is a mineral found in feldspat and clay, in combination with water becomes calcium hydroxid.
Calcium hydroxid or hydrated lime ("Kalkwasser")is used today to raise the calcium concentration and pH value. e.g.in aquarium
But what for was it used when the blocks were shaped?
The foto shows a huge block covered with a vertical (not horizontal)layer of paste like glue. Or liquid gypsum that hardened. The block was found under 1m of clay on the very steep base of sun pyramid (before coming to sonda 5)text by G.Lukacs