XXchok-ston (abhneghir (compare Eben-ezer, ebhen ha-`ezer, "stone of the help," 1 Sam 7:12)): In Isa 27:9 we have: "Therefore by this shall the iniquity of Jacob be forgiven, and this is all the fruit of taking away his sin: that he maketh all the stones of the altar as chalkstones that are beaten in sunder, so that the Asherim and the sun-images shall rise no more." Abhne-ghir is compounded of ebhen, "stone," which occurs in many passages, and gir or gir, "lime" (compare Arabic jir , "gypsum" or "quicklime"), which occurs only here and in Dan 5:5: "wrote .... upon the plaster (gir) of the wall of the kings palace." Nearly all the rock of Israel is limestone. When limestone is burned, it is converted into lime, which is easily broken into pieces, and, if allowed to remain open to the air, becomes slaked by the moisture of the atmosphere and crumbles into dust. The reference is to the destruction of the altar. It may mean that the altar will be burned so that the stones will become lime, or, more probably, that the stones of the altar will be broken as chalkstones (i.e. lumps of quicklime) are broken. There is no doubt that lime was known to the Egyptians, Assyrians and Hebrews, though clay, with or without straw, was more commonly used in building. Even bitumen ("slime") appears to have been used for mortar.
Alfred Ely Day